Radio resource control RRC message processing method, apparatus, and system

ABSTRACT

Embodiments of the present invention relate to a radio resource control RRC message processing method, apparatus, and system. The method includes: setting up, by a first serving node, a connection to a first anchor node, and setting up, by the first anchor node, a connection to a mobility management entity MME; receiving, by the first serving node, a radio resource control RRC message sent by first user equipment UE, where the RRC message includes an RRC message carried by a signaling radio bearer SRB1 or an RRC message carried by an SRB2; and sending, by the first serving node, the RRC message to the first anchor node.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.16/446,319, filed on Jun. 19, 2019, which is a continuation of U.S.patent application Ser. No. 16/355,404, filed on Mar. 15, 2019, which isa continuation of U.S. patent application Ser. No. 15/493,362, filed onApr. 21, 2017, now U.S. Pat. No. 10,257,881, which is a continuation ofInternational Patent Application No. PCT/CN2014/089300, filed on Oct.23, 2014. All of the afore-mentioned patent applications are herebyincorporated by reference in their entireties.

TECHNICAL FIELD

The present invention relates to the field of mobile communications, andin particular, to a radio resource control RRC message processingmethod, apparatus, and system.

BACKGROUND

With an increasing quantity of user equipment (UE, User Equipment), anexisting wireless communications system cannot meet a wirelesscommunication requirement of a user. Therefore, there is an urgent needto increase a system capacity of the wireless communications system. Thesystem capacity may be increased by adding base stations. Typically,many small cells are deployed densely in a macro cell, to form moremicro cells. However, most UE is connected to a base station, and thebase station provides a wireless communication service for the UE. Forbrevity of description, a network device that provides a wirelesscommunication service for UE is referred to as a serving node of the UE,and the serving node may be specifically a base station.

In the prior art, when UE is handed over from a cell to another cell, orwhen UE is handed over from a coverage area of a base station to acoverage area of another base station, or when UE finds a radio linkfailure (RLF, Radio Link Failure), a serving node handover may beperformed on the UE, that is, the serving node of the UE is changed froma base station to another base station. Because the serving node and amobility management entity (MME, Mobility management entity) areconnected by using a control plane interface, and the serving node and aserving gateway (SGW, Serving Gateway) are connected by using a userplane interface, after the serving node handover is performed on the UE,signaling needs to be sent between a new serving node and the MME toupdate an S1 control plane connection between the serving node and theMME, and signaling also needs to be sent between the MME and the SGW toupdate an S1 user plane connection between the serving node and the SGW.Therefore, each handover process brings at least four messages. Whendeployment density of a base station quantity increases, a handoverquantity increases sharply, and consequently, signaling load of a corenetwork increases sharply. In addition, each serving node and the MMEare connected by using a control plane interface. When the MME has apaging message to be sent, the MME sends the paging message to all basestations in a tracking area (TA, tracking area) area corresponding tothe paging message. As a result, signaling load of a core networkincreases sharply.

SUMMARY

Embodiments of the present invention provide an RRC message processingmethod, apparatus, and system, so as to effectively reduce signalingload of a core network.

A first aspect provides an RRC message processing system, where thesystem includes a first serving node, a first anchor node, and amobility management entity MME, the first serving node sets up aconnection to the first anchor node, and the first anchor node sets up aconnection to the MME;

the first serving node is configured to: receive a radio resourcecontrol RRC message sent by first user equipment UE, where the RRCmessage includes an RRC message carried by a signaling radio bearer SRB1or an RRC message carried by an SRB2; and send the RRC message to thefirst anchor node; and

the first anchor node is configured to: process, by using a first PacketData Convergence Protocol PDCP layer entity, the RRC message carried bythe SRB1 and then send a processed message to an RRC layer entity; orprocess, by using a second PDCP layer entity, the RRC message carried bythe SRB2 and then send a processed message to the RRC layer entity.

A second aspect provides an RRC message processing apparatus, where theapparatus is disposed on a serving node, a first serving node sets up aconnection to a first anchor node, and the first anchor node sets up aconnection to a mobility management entity MME; and

the apparatus includes:

a receiving unit, configured to receive an RRC message sent by firstuser equipment UE, where the RRC message includes an RRC message carriedby a signaling radio bearer SRB1 or an RRC message carried by an SRB2;and

a sending unit, configured to: send the RRC message received by thereceiving unit to the first anchor node, so that a first Packet DataConvergence Protocol PDCP layer entity of the first anchor nodeprocesses the RRC message carried by the SRB1 and then sends a processedmessage to an RRC layer entity of the first anchor node, or a secondPDCP layer entity of the first anchor node processes the RRC messagecarried by the SRB2 and then sends a processed message to an RRC layerentity of the first anchor node.

With reference to the second aspect, in a first implementation manner ofthe second aspect, the receiving unit is further configured to receivean RRC message sent by the first anchor node, the RRC message includesan RRC message carried by an SRB1 or an RRC message carried by an SRB2,and the apparatus further includes:

a first processing unit, configured to process, by using a first RadioLink Control RLC layer entity of the first serving node, the RRC messagecarried by the SRB1, so that the sending unit sends a processed messageto the first UE; and

a second processing unit, configured to process, by using a second RLClayer entity of the first serving node, the RRC message carried by theSRB2, so that the sending unit sends a processed message to the firstUE.

With reference to the second aspect or the first implementation mannerof the second aspect, in a second implementation manner of the secondaspect, the apparatus further includes:

a message generation unit, configured to generate, by using an RRC layerentity of the first serving node, an RRC message carried by an SRB0, sothat the sending unit sends the RRC message carried by the SRB0 to thefirst UE and/or the first anchor node.

With reference to the second aspect or the first implementation mannerof the second aspect, in a third implementation manner of the secondaspect, the RRC message further includes an RRC message carried by anSRB0; the sending unit is further configured to send first indicationinformation to the first anchor node, where the first indicationinformation is used by the first anchor node to identify, according tothe first indication information, that the RRC message is the RRCmessage carried by the SRB0, and to perform processing by using the RRClayer entity of the first anchor node: and the receiving unit is furtherconfigured to receive first indication information sent by the firstanchor node, where the first indication information is used by the firstserving node to identify, according to the first indication information,that the RRC message is the RRC message carried by the SRB0, and toperform processing by using an RRC layer entity of the first servingnode.

With reference to the second aspect or the first implementation mannerof the second aspect, in a fourth implementation manner of the secondaspect, the sending unit is further configured to send second indicationinformation to the first anchor node, where the second indicationinformation is used by the first anchor node to identify, according tothe second indication information, that the RRC message is the RRCmessage carried by the SRB1; and the receiving unit is furtherconfigured to receive second indication information sent by the firstanchor node, where the second indication information is used by thefirst serving node to identify, according to the second indicationinformation, that the RRC message is the RRC message carried by theSRB1.

With reference to the second aspect or the first implementation mannerof the second aspect, in a fifth implementation manner of the secondaspect, the sending unit is further configured to send third indicationinformation to the first anchor node, where the third indicationinformation is used by the first anchor node to identify, according tothe third indication information, that the RRC message is the RRCmessage carried by the SRB2; and the receiving unit is furtherconfigured to receive third indication information sent by the firstanchor node, where the third indication information is used by the firstserving node to identify, according to the third indication information,that the RRC message is the RRC message carried by the SRB2.

With reference to the second aspect, in a sixth implementation manner ofthe second aspect, the apparatus further includes: a first processingunit, configured to: before the sending unit sends the RRC message tothe first anchor node, process, by using a first RLC layer entity of thefirst serving node, the RRC message carried by the SRB1; and

a second processing unit, configured to: before the sending unit sendsthe RRC message to the first anchor node, process, by using a second RLClayer entity of the first serving node, the RRC message carried by theSRB2.

With reference to the first implementation manner of the second aspect,in a seventh implementation manner of the second aspect, the sendingunit is specifically configured to: send the RRC message processed bythe first processing unit to the first UE by using a Media AccessControl MAC layer and a physical layer, or send the RRC messageprocessed by the second processing unit to the first UE by using a MAClayer and a physical layer.

With reference to the first implementation manner of the second aspect,in an eighth implementation manner of the second aspect, the sendingunit is specifically configured to: send the RRC message processed bythe first processing unit to the first UE, so that a first PDCP layerentity of the first UE processes the RRC message carried by the SRB1 andthen sends the processed message to an RRC layer entity; or send the RRCmessage processed by the second processing unit to the first UE, so thata second PDCP layer entity of the first UE processes the RRC messagecarried by the SRB2 and then sends the processed message to the RRClayer entity.

With reference to the first implementation manner of the second aspect,in a ninth implementation manner of the second aspect, the RRC messagefurther includes an RRC message carried by an SRB0, the RRC messagecarried by the SRB0 is specifically an RRC connection request message oran RRC connection setup message, and the RRC message carried by the SRB1is specifically an RRC connection setup complete message;

the receiving unit is specifically configured to receive the RRCconnection request message sent by the first UE, where the RRCconnection request message is an RRC connection request message that issent by the first UE to the first serving node after the first UEreceives a system message sent by means of broadcast by the firstserving node, sends a random access message to the first serving nodeaccording to the system message, and receives a random access responsemessage sent by the first serving node;

the sending unit is specifically configured to forward the RRCconnection request message received by the receiving unit to the firstanchor node;

the receiving unit is further configured to receive the RRC connectionsetup message sent by the first anchor node, where the RRC connectionsetup message is the RRC connection setup message generated by the firstanchor node according to the received RRC connection request message;

the sending unit is further configured to send the RRC connection setupmessage received by the receiving unit to the first UE;

the receiving unit is further configured to receive the RRC connectionsetup complete message sent by the first UE; and

the sending unit is further configured to send the RRC connection setupcomplete message received by the receiving unit to the first anchornode, to set up an RRC connection for the first anchor node and thefirst UE.

With reference to the first implementation manner of the second aspect,in a tenth implementation manner of the second aspect, the RRC messagecarried by the SRB1 is specifically an RRC connection reconfigurationmessage or an RRC connection reconfiguration complete message;

the sending unit is specifically configured to send a beareraddition/modification confirmation message to the first anchor node,where the bearer addition/modification confirmation message is thebearer addition/modification confirmation message that is generated bythe first serving node according to a bearer addition/modificationrequest message after the first serving node receives the beareraddition/modification request message sent by the first anchor node;

the receiving unit is specifically configured to receive the RRCconnection reconfiguration message sent by the first anchor node;

the sending unit is further configured to send the RRC connectionreconfiguration message received by the receiving unit to the first UE;

the receiving unit is further configured to receive the RRC connectionreconfiguration complete message sent by the first UE; and

the sending unit is further configured to send the RRC connectionreconfiguration complete message received by the receiving unit to thefirst anchor node, so that the first anchor node sends a beareraddition/modification complete message to the first serving nodeaccording to the RRC connection reconfiguration complete message.

With reference to the first implementation manner of the second aspect,in an eleventh implementation manner of the second aspect, the RRCmessage carried by the SRB1 is specifically an RRC connectionreconfiguration message or an RRC connection reconfiguration completemessage;

the receiving unit is specifically configured to receive the RRCconnection reconfiguration message sent by the first anchor node, wherethe RRC connection reconfiguration message is the RRC connectionreconfiguration message that is sent by the first anchor node after thefirst serving node receives a bearer addition/modification requestmessage sent by the first anchor node and sends a beareraddition/modification confirmation message to the first anchor node;

the sending unit is specifically configured to send the RRC connectionreconfiguration message received by the receiving unit to the first UE;

the receiving unit is further configured to receive the RRC connectionreconfiguration complete message sent by the first UE;

the sending unit is further configured to send the RRC connectionreconfiguration complete message received by the receiving unit to thefirst anchor node; and

the receiving unit is further configured to receive a bearaddition/modification complete message sent by the first anchor node.

With reference to the first implementation manner of the second aspect,in a twelfth implementation manner of the second aspect, the RRC messagecarried by the SRB1 is specifically an RRC connection reconfigurationmessage;

the receiving unit is specifically configured to receive the RRCconnection reconfiguration message sent by the first anchor node, wherethe RRC connection reconfiguration message is the RRC connectionreconfiguration message that is sent by the first anchor node after asecond anchor node or a neighboring base station receives a handoverrequest message sent by the first anchor node and sends a handoverrequest confirmation message to the first anchor node, and the firstserving node belongs to the first anchor node; and

the sending unit is specifically configured to send the RRC connectionreconfiguration message received by the receiving unit to the first UE.

With reference to the first implementation manner of the second aspect,in a thirteenth implementation manner of the second aspect, the RRCmessage further includes an RRC message carried by an SRB0, the RRCmessage carried by the SRB0 is specifically an RRC connection re-setuprequest message or an RRC connection re-setup message, and the RRCmessage carried by the SRB1 is specifically an RRC connection re-setupcomplete message;

the receiving unit is specifically configured to receive the RRCconnection re-setup request message sent by the first UE, where the RRCconnection re-setup request message is the RRC connection re-setuprequest message that is sent by the first UE after the first UE finds aradio link failure RLF, receives a system message sent by means ofbroadcast by the first serving node, sends a random access message tothe first serving node according to the system message, and receives arandom access response message sent by the first serving node;

the sending unit is specifically configured to send the RRC connectionre-setup request message received by the receiving unit to the firstanchor node;

the receiving unit is further configured to receive the RRC connectionre-setup message sent by the first anchor node;

the sending unit is further configured to send the RRC connectionre-setup message received by the receiving unit to the first UE;

the receiving unit is further configured to receive the RRC connectionre-setup complete message sent by the first UE; and

the sending unit is further configured to send the RRC connectionre-setup complete message received by the receiving unit to the firstanchor node, to set up an RRC connection for the first anchor node andthe first UE.

A third aspect provides an RRC message processing apparatus, where theapparatus is disposed on an anchor node, a first serving node sets up aconnection to a first anchor node, the first anchor node sets up aconnection to a mobility management entity MME, and the apparatusincludes:

a sending unit, configured to send a radio resource control RRC messageto the first serving node, where the RRC message includes an RRC messagecarried by a signaling radio bearer SRB1 or an RRC message carried by anSRB2.

With reference to the third aspect, in a first implementation manner ofthe third aspect, the apparatus further includes:

a receiving unit, configured to receive an RRC message sent by the firstserving node;

a first packet data processing unit, configured to process, by using afirst Packet Data Convergence Protocol PDCP layer entity of the firstanchor node, an RRC message that is carried by an SRB1 and received bythe receiving unit and then send a processed message to an RRC layerentity of the first anchor node; and

a second packet data processing unit, configured to process, by using asecond PDCP layer entity of the first anchor node, an RRC message thatis carried by an SRB2 and received by the receiving unit and then send aprocessed message to the RRC layer entity of the first anchor node.

With reference to the third aspect or the first implementation manner ofthe third aspect, in a second implementation manner of the third aspect,the apparatus further includes:

a first message generation unit, configured to generate, by using theRRC layer entity of the first anchor node, the RRC message carried bythe SRB1 or the RRC message carried by the SRB2, where

the sending unit is specifically configured to send, to the firstserving node, the RRC message that is carried by the SRB1 and generatedby the first message generation unit or the RRC message that is carriedby the SRB2 and generated by the first message generation unit.

With reference to the third aspect or the first implementation manner ofthe third aspect, in a third implementation manner of the third aspect,the RRC message further includes an RRC message carried by an SRB0, andthe receiving unit is further configured to receive first indicationinformation sent by the first serving node; and

the apparatus further includes:

an identification unit, configured to: identify, according to the firstindication information received by the receiving unit, that the RRCmessage is the RRC message carried by the SRB0, and perform processingby using the RRC layer entity of the first anchor node, where

the sending unit is further configured to send first indicationinformation to the first serving node, where the first indicationinformation is used by the first serving node to identify, according tothe first indication information, that the RRC message is the RRCmessage carried by the SRB0, and to perform processing by using an RRClayer entity of the first serving node.

With reference to the third aspect or the first implementation manner ofthe third aspect, in a fourth implementation manner of the third aspect,the receiving unit is further configured to receive second indicationinformation sent by the first serving node; and

the apparatus further includes:

an identification unit, configured to identify, according to the secondindication information received by the receiving unit, that the RRCmessage is the RRC message carried by the SRB1, where

the sending unit is further configured to send second indicationinformation to the first serving node, where the second indicationinformation is used by the first serving node to identify, according tothe second indication information, that the RRC message is the RRCmessage carried by the SRB1.

With reference to the third aspect or the first implementation manner ofthe third aspect, in a fifth implementation manner of the third aspect,the receiving unit is further configured to receive third indicationinformation sent by the first serving node; and

the apparatus further includes:

an identification unit, configured to identify, according to the thirdindication information received by the receiving unit, that the RRCmessage is the RRC message carried by the SRB2, where

the sending unit is further configured to send third indicationinformation to the first serving node, where the third indicationinformation is used by the first serving node to identify, according tothe third indication information, that the RRC message is the RRCmessage carried by the SRB2.

With reference to the first implementation manner of the third aspect,in a sixth implementation manner of the third aspect, the RRC messagefurther includes an RRC message carried by an SRB0, the RRC messagecarried by the SRB0 is specifically an RRC connection request message oran RRC connection setup message, and the RRC message carried by the SRB1is specifically an RRC connection setup complete message;

the receiving unit is specifically configured to receive the RRCconnection request message forwarded by the first serving node, wherethe RRC connection request message is an RRC connection request messagethat is sent by the first UE to the first serving node after the firstUE receives a system message sent by means of broadcast by the firstserving node, sends a random access message to the first serving nodeaccording to the system message, and receives a random access responsemessage sent by the first serving node; and

the apparatus further includes:

a second message generation unit, configured to generate the RRCconnection setup message according to the RRC connection request messagereceived by the receiving unit, where

the sending unit is specifically configured to send, to the firstserving node, the RRC connection setup message generated by the secondmessage generation unit, so that the first serving node sends the RRCconnection setup message to the first UE; and

the receiving unit is further configured to receive the RRC connectionsetup complete message sent by the first serving node, to set up an RRCconnection for the first anchor node and the first UE, where the RRCconnection setup complete message is an RRC connection setup completemessage that is sent by the first UE to the first serving node after thefirst UE receives the RRC connection setup message.

With reference to the first implementation manner of the third aspect,in a seventh implementation manner of the third aspect, the RRC messagecarried by the SRB1 is specifically an RRC connection reconfigurationmessage or an RRC connection reconfiguration complete message;

the receiving unit is specifically configured to receive a beareraddition/modification confirmation message sent by the first servingnode, where the bearer addition/modification confirmation message is thebearer addition/modification confirmation message that is generated bythe first serving node according to a bearer addition/modificationrequest message after the first anchor node sends the beareraddition/modification request message to the first serving node;

the sending unit is specifically configured to send the RRC connectionreconfiguration message to the first serving node, so that the firstserving node sends the RRC connection reconfiguration message to thefirst UE; and

the receiving unit is further configured to receive the RRC connectionreconfiguration complete message sent by the first serving node, wherethe RRC connection reconfiguration complete message is the RRCconnection reconfiguration complete message that is sent by the first UEto the first serving node after the first UE receives the RRC connectionreconfiguration message, where the first anchor node sends a beareraddition/modification complete message to the first serving nodeaccording to the RRC connection reconfiguration complete message.

With reference to the first implementation manner of the third aspect,in an eighth implementation manner of the third aspect, the RRC messagecarried by the SRB1 is specifically an RRC connection reconfigurationmessage or an RRC connection reconfiguration complete message;

the sending unit is specifically configured to send the RRC connectionreconfiguration message to the first serving node, where the RRCconnection reconfiguration message is the RRC connection reconfigurationmessage that is sent by the first anchor node to the first serving nodeafter the first anchor node sends a bearer addition/modification requestmessage to the first serving node and receives a beareraddition/modification confirmation message sent by the first servingnode;

the receiving unit is specifically configured to receive the RRCconnection reconfiguration complete message sent by the first servingnode, where the RRC connection reconfiguration complete message is theRRC connection reconfiguration complete message that is sent by thefirst UE and that is received by the first serving node after the firstserving node receives the RRC connection reconfiguration message sent bythe first anchor node and sends the RRC connection reconfigurationmessage to the first UE; and

the sending unit is further configured to send a bearaddition/modification complete message to the first serving node.

With reference to the first implementation manner of the third aspect,in a ninth implementation manner of the third aspect, the RRC messagecarried by the SRB1 is specifically an RRC connection reconfigurationmessage; and

the sending unit is specifically configured to send the RRC connectionreconfiguration message to the first serving node, so that the firstserving node sends the RRC connection reconfiguration message to thefirst UE, where the RRC connection reconfiguration message is the RRCconnection reconfiguration message that is sent by the first anchor nodeafter a second anchor node or a neighboring base station receives ahandover request message sent by the first anchor node and sends ahandover request confirmation message to the first anchor node, and thefirst serving node belongs to the first anchor node.

With reference to the first implementation manner of the third aspect,in a tenth implementation manner of the third aspect, the RRC messagefurther includes an RRC message carried by an SRB0, the RRC messagecarried by the SRB0 is specifically an RRC connection re-setup requestmessage or an RRC connection re-setup message, and the RRC messagecarried by the SRB1 is specifically an RRC connection re-setup completemessage;

the receiving unit is specifically configured to receive the RRCconnection re-setup request message sent by the first serving node,where the RRC connection re-setup request message is the RRC connectionre-setup request message that is sent by the first UE to the firstserving node after the first UE finds a radio link failure RLF, receivesa system message sent by means of broadcast by the first serving node,sends a random access message to the first serving node according to thesystem message, and receives a random access response message sent bythe first serving node;

the sending unit is specifically configured to send the RRC connectionre-setup message to the first serving node, so that the first servingnode sends the RRC connection re-setup message to the first UE; and

the receiving unit is further configured to receive the RRC connectionre-setup complete message sent by the first serving node, to set up anRRC connection for the first anchor node and the first UE, where the RRCconnection re-setup complete message is the RRC connection re-setupcomplete message that is sent by the first UE and received by the firstserving node.

A fourth aspect provides a serving node, where the serving node sets upa connection to a first anchor node, and the first anchor node sets up aconnection to a mobility management entity MME;

the serving node includes a transmitter and a receiver;

the receiver is configured to receive a radio resource control RRCmessage sent by first user equipment UE, where the RRC message includesan RRC message carried by a signaling radio bearer SRB1 or an RRCmessage carried by an SRB2; and

the transmitter is configured to: send the RRC message received by thereceiver to the first anchor node, so that a first Packet DataConvergence Protocol PDCP layer entity of the first anchor nodeprocesses the RRC message carried by the SRB1 and then sends a processedmessage to an RRC layer entity of the first anchor node, or a secondPDCP layer entity of the first anchor node processes the RRC messagecarried by the SRB2 and then sends a processed message to an RRC layerentity of the first anchor node.

A fifth aspect provides an anchor node, where a first serving node setsup a connection to the anchor node, the anchor node sets up a connectionto a mobility management entity MME, and the anchor includes atransmitter; and

the transmitter is configured to send a radio resource control RRCmessage to the first serving node, where the RRC message includes an RRCmessage carried by a signaling radio bearer SRB1 or an RRC messagecarried by an SRB2.

A sixth aspect provides an RRC message processing method, where a firstserving node sets up a connection to a first anchor node, and the firstanchor node sets up a connection to a mobility management entity MME;and

the method includes:

receiving, by the first serving node, a radio resource control RRCmessage sent by first user equipment UE, where the RRC message includesan RRC message carried by a signaling radio bearer SRB1 or an RRCmessage carried by an SRB2; and

sending, by the first serving node, the RRC message to the first anchornode, so that a first Packet Data Convergence Protocol PDCP layer entityof the first anchor node processes the RRC message carried by the SRB1and then sends a processed message to an RRC layer entity of the firstanchor node, or a second PDCP layer entity of the first anchor nodeprocesses the RRC message carried by the SRB2 and then sends a processedmessage to an RRC layer entity of the first anchor node.

With reference to the sixth aspect, in a first implementation manner ofthe sixth aspect, the method further includes:

receiving, by the first serving node, an RRC message sent by the firstanchor node, where the RRC message includes an RRC message carried by anSRB1 or an RRC message carried by an SRB2; and

processing, by a first Radio Link Control RLC layer entity of the firstserving node, the RRC message carried by the SRB1 and then sending aprocessed message to the first UE; or processing, by a second RLC layerentity of the first serving node, the RRC message carried by the SRB2and then sending a processed message to the first UE.

With reference to the sixth aspect or the first implementation manner ofthe sixth aspect, in a second implementation manner of the sixth aspect,the method further includes: generating, by an RRC layer entity of thefirst serving node, an RRC message carried by an SRB0, and sending theRRC message carried by the SRB0 to the first UE and/or the first anchornode.

With reference to the sixth aspect or the first implementation manner ofthe sixth aspect, in a third implementation manner of the sixth aspect,the RRC message further includes an RRC message carried by an SRB0, andthe method further includes: sending, by the first serving node, firstindication information to the first anchor node, where the firstindication information is used by the first anchor node to identify,according to the first indication information, that the RRC message isthe RRC message carried by the SRB0, and to perform processing by usingthe RRC layer entity of the first anchor node; or receiving, by thefirst serving node, first indication information sent by the firstanchor node, where the first indication information is used by the firstserving node to identify, according to the first indication information,that the RRC message is the RRC message carried by the SRB0, and toperform processing by using an RRC layer entity of the first servingnode.

With reference to the sixth aspect or the first implementation manner ofthe sixth aspect, in a fourth implementation manner of the sixth aspect,the method further includes: sending, by the first serving node, secondindication information to the first anchor node, where the secondindication information is used by the first anchor node to identify,according to the second indication information, that the RRC message isthe RRC message carried by the SRB1; or receiving, by the first servingnode, second indication information sent by the first anchor node, wherethe second indication information is used by the first serving node toidentify, according to the second indication information, that the RRCmessage is the RRC message carried by the SRB1.

With reference to the sixth aspect or the first implementation manner ofthe sixth aspect, in a fifth implementation manner of the sixth aspect,the method further includes: sending, by the first serving node, thirdindication information to the first anchor node, where the thirdindication information is used by the first anchor node to identify,according to the third indication information, that the RRC message isthe RRC message carried by the SRB2; or receiving, by the first servingnode, third indication information sent by the first anchor node, wherethe third indication information is used by the first serving node toidentify, according to the third indication information, that the RRCmessage is the RRC message carried by the SRB2.

With reference to the sixth aspect, in a sixth implementation manner ofthe sixth aspect, before the sending, by the first serving node, the RRCmessage to the first anchor node, the method further includes:processing, by a first RLC layer entity of the first serving node, theRRC message carried by the SRB1; or processing, by the second RLC layerentity, the RRC message carried by the SRB2.

With reference to the first implementation manner of the sixth aspect,in a seventh implementation manner of the sixth aspect, the processing,by a first RLC layer entity of the first serving node, the RRC messagecarried by the SRB1 and then sending a processed message to the firstUE; or processing, by a second RLC layer entity of the first servingnode, the RRC message carried by the SRB2 and then sending a processedmessage to the first UE includes: processing, by the first RLC layerentity of the first serving node, the RRC message carried by the SRB1and then sending the processed message to the first UE by using a MediaAccess Control MAC layer and a physical layer; or processing, by thesecond RLC layer entity of the first serving node, the RRC messagecarried by the SRB2 and then sending the processed message to the firstUE by using a MAC layer and a physical layer.

With reference to the first implementation manner of the sixth aspect,in an eighth implementation manner of the sixth aspect, the processing,by a first RLC layer entity of the first serving node, the RRC messagecarried by the SRB1 and then sending a processed message to the firstUE; or processing, by a second RLC layer entity of the first servingnode, the RRC message carried by the SRB2 and then sending a processedmessage to the first UE includes: processing, by the first RLC layerentity of the first serving node, the RRC message carried by the SRB1and then sending the processed message to the first UE, so that a firstPDCP layer entity of the first UE processes the RRC message carried bythe SRB1 and then sends the processed message to an RRC layer entity; orprocessing, by the second RLC layer entity of the first serving node,the RRC message carried by the SRB2 and then sending the processedmessage to the first UE, so that a second PDCP layer entity of the firstUE processes the RRC message carried by the SRB2 and then sends theprocessed message to the RRC layer entity.

With reference to the first implementation manner of the sixth aspect,in a ninth implementation manner of the sixth aspect, the RRC messagefurther includes an RRC message carried by an SRB0, the RRC messagecarried by the SRB0 is specifically an RRC connection request message oran RRC connection setup message, and the RRC message carried by the SRB1is specifically an RRC connection setup complete message; and

the method further includes:

receiving, by the first serving node, the RRC connection request messagesent by the first UE, where the RRC connection request message is an RRCconnection request message that is sent by the first UE to the firstserving node after the first UE receives a system message sent by meansof broadcast by the first serving node, sends a random access message tothe first serving node according to the system message, and receives arandom access response message sent by the first serving node;

forwarding, by the first serving node, the RRC connection requestmessage to the first anchor node;

receiving, by the first serving node, the RRC connection setup messagesent by the first anchor node, where the RRC connection setup message isthe RRC connection setup message generated by the first anchor nodeaccording to the received RRC connection request message;

sending, by the first serving node, the RRC connection setup message tothe first UE;

receiving, by the first serving node, the RRC connection setup completemessage sent by the first UE; and

sending, by the first serving node, the RRC connection setup completemessage to the first anchor node, to set up an RRC connection for thefirst anchor node and the first UE.

With reference to the first implementation manner of the sixth aspect,in a tenth implementation manner of the sixth aspect, the RRC messagecarried by the SRB1 is specifically an RRC connection reconfigurationmessage or an RRC connection reconfiguration complete message; and

the method further includes;

sending, by the first serving node, a bearer addition/modificationconfirmation message to the first anchor node, where the beareraddition/modification confirmation message is the beareraddition/modification confirmation message that is generated by thefirst serving node according to a bearer addition/modification requestmessage after the first serving node receives the beareraddition/modification request message sent by the first anchor node;

receiving the RRC connection reconfiguration message sent by the firstanchor node;

sending the RRC connection reconfiguration message to the first UE;

receiving the RRC connection reconfiguration complete message sent bythe first UE; and

sending the RRC connection reconfiguration complete message to the firstanchor node, so that the first anchor node sends a beareraddition/modification complete message to the first serving nodeaccording to the RRC connection reconfiguration complete message.

With reference to the first implementation manner of the sixth aspect,in an eleventh implementation manner of the sixth aspect, the RRCmessage carried by the SRB1 is specifically an RRC connectionreconfiguration message or an RRC connection reconfiguration completemessage; and

the method further includes:

receiving, by the first serving node, the RRC connection reconfigurationmessage sent by the first anchor node, where the RRC connectionreconfiguration message is the RRC connection reconfiguration messagethat is sent by the first anchor node after the first serving nodereceives a bearer addition/modification request message sent by thefirst anchor node and sends a bearer addition/modification confirmationmessage to the first anchor node;

sending, by the first serving node, the RRC connection reconfigurationmessage to the first UE;

receiving, by the first serving node, the RRC connection reconfigurationcomplete message sent by the first UE;

sending, by the first serving node, the RRC connection reconfigurationcomplete message to the first anchor node; and

receiving, by the first serving node, a bear addition/modificationcomplete message sent by the first anchor node.

With reference to the first implementation manner of the sixth aspect,in a twelfth implementation manner of the sixth aspect, the RRC messagecarried by the SRB1 is specifically an RRC connection reconfigurationmessage; and

the method further includes:

receiving, by the first serving node, the RRC connection reconfigurationmessage sent by the first anchor node, where the RRC connectionreconfiguration message is the RRC connection reconfiguration messagethat is sent by the first anchor node after a second anchor node or aneighboring base station receives a handover request message sent by thefirst anchor node and sends a handover request confirmation message tothe first anchor node, and the first serving node belongs to the firstanchor node; and

sending, by the first serving node, the RRC connection reconfigurationmessage to the first UE.

With reference to the first implementation manner of the sixth aspect,in a thirteenth implementation manner of the sixth aspect, the RRCmessage further includes an RRC message carried by an SRB0, the RRCmessage carried by the SRB0 is specifically an RRC connection re-setuprequest message or an RRC connection re-setup message, and the RRCmessage carried by the SRB1 is specifically an RRC connection re-setupcomplete message; and

the method further includes:

receiving, by the first serving node, the RRC connection re-setuprequest message sent by the first UE, where the RRC connection re-setuprequest message is the RRC connection re-setup request message that issent by the first UE after the first UE finds a radio link failure RLF,receives a system message sent by means of broadcast by the firstserving node, sends a random access message to the first serving nodeaccording to the system message, and receives a random access responsemessage sent by the first serving node;

sending, by the first serving node, the RRC connection re-setup requestmessage to the first anchor node;

receiving, by the first serving node, the RRC connection re-setupmessage sent by the first anchor node;

sending, by the first serving node, the RRC connection re-setup messageto the first UE;

receiving, by the first serving node, the RRC connection re-setupcomplete message sent by the first UE; and

sending, by the first serving node, the RRC connection re-setup completemessage to the first anchor node, to set up an RRC connection for thefirst anchor node and the first UE.

A seventh aspect provides an RRC message processing method, where afirst serving node sets up a connection to a first anchor node, thefirst anchor node sets up a connection to a mobility management entityMME, and the method includes:

sending, by the first anchor node, a radio resource control RRC messageto the first serving node, where the RRC message includes an RRC messagecarried by a signaling radio bearer SRB1 or an RRC message carried by anSRB2.

With reference to the seventh aspect, in a first implementation mannerof the seventh aspect, the method further includes:

receiving, by the first anchor node, an RRC message sent by the firstserving node; and processing, by a first Packet Data ConvergenceProtocol PDCP layer entity of the first anchor node, an RRC messagecarried by the SRB1 and then sending a processed message to an RRC layerentity of the first anchor node; or processing, by a second PDCP layerentity of the first anchor node, an RRC message carried by the SRB2 andthen sending a processed message to an RRC layer entity of the firstanchor node.

With reference to the seventh aspect or the first implementation mannerof the seventh aspect, in a second implementation manner of the seventhaspect, the method further includes: generating, by the RRC layer entityof the first anchor node, the RRC message carried by an SRB1 or the RRCmessage carried by the SRB2; and sending, to the first serving node, theRRC message carried by the SRB1 or the RRC message carried by the SRB2.

With reference to the seventh aspect or the first implementation mannerof the seventh aspect, in a third implementation manner of the seventhaspect, the RRC message further includes an RRC message carried by anSRB0, and the method further includes: receiving, by the first anchornode, first indication information sent by the first serving node, wherethe first indication information is used by the first anchor node toidentify, according to the first indication information, that the RRCmessage is the RRC message carried by the SRB0, and to performprocessing by using the RRC layer entity of the first anchor node: orsending, by the first anchor node, first indication information to thefirst serving node, where the first indication information is used bythe first serving node to identify, according to the first indicationinformation, that the RRC message is the RRC message carried by theSRB0, and to perform processing by using an RRC layer entity of thefirst serving node.

With reference to the seventh aspect or the first implementation mannerof the seventh aspect, in a fourth implementation manner of the seventhaspect, the method further includes: receiving, by the first anchornode, second indication information sent by the first serving node,where the second indication information is used by the first anchor nodeto identify, according to the second indication information, that theRRC message is the RRC message carried by the SRB1; or sending, by thefirst anchor node, second indication information to the first servingnode, where the second indication information is used by the firstserving node to identify, according to the second indicationinformation, that the RRC message is the RRC message carried by theSRB1.

With reference to the seventh aspect or the first implementation mannerof the seventh aspect, in a fifth implementation manner of the seventhaspect, the method further includes: receiving, by the first anchornode, third indication information sent by the first serving node, wherethe third indication information is used by the first anchor node toidentify, according to the third indication information, that the RRCmessage is the RRC message carried by the SRB2; or sending, by the firstanchor node, third indication information to the first serving node,where the third indication information is used by the first serving nodeto identify, according to the third indication information, that the RRCmessage is the RRC message carried by the SRB2.

With reference to the first implementation manner of the seventh aspect,in a sixth implementation manner of the seventh aspect, the RRC messagefurther includes an RRC message carried by an SRB0, the RRC messagecarried by the SRB0 is specifically an RRC connection request message oran RRC connection setup message, and the RRC message carried by the SRB1is specifically an RRC connection setup complete message; and

the method further includes:

receiving, by the first anchor node, the RRC connection request messageforwarded by the first serving node, where the RRC connection requestmessage is an RRC connection request message that is sent by the firstUE to the first serving node after the first UE receives a systemmessage sent by means of broadcast by the first serving node, sends arandom access message to the first serving node according to the systemmessage, and receives a random access response message sent by the firstserving node;

generating, by the first anchor node, the RRC connection setup messageaccording to the RRC connection request message;

sending, by the first anchor node, the RRC connection setup message tothe first serving node, so that the first serving node sends the RRCconnection setup message to the first UE; and

receiving, by the first anchor node, the RRC connection setup completemessage sent by the first serving node, to set up an RRC connection forthe first anchor node and the first UE, where the RRC connection setupcomplete message is an RRC connection setup complete message that issent by the first UE to the first serving node after the first UEreceives the RRC connection setup message.

With reference to the first implementation manner of the seventh aspect,in a seventh implementation manner of the seventh aspect, the RRCmessage carried by the SRB1 is specifically an RRC connectionreconfiguration message or an RRC connection reconfiguration completemessage; and

the method further includes:

receiving, by the first anchor node, a bearer addition/modificationconfirmation message sent by the first serving node, where the beareraddition/modification confirmation message is the beareraddition/modification confirmation message that is generated by thefirst serving node according to a bearer addition/modification requestmessage after the first anchor node sends the beareraddition/modification request message to the first serving node;

sending, by the first anchor node, the RRC connection reconfigurationmessage to the first serving node, so that the first serving node sendsthe RRC connection reconfiguration message to the first UE; and

receiving, by the first anchor node, the RRC connection reconfigurationcomplete message sent by the first serving node, where the RRCconnection reconfiguration complete message is the RRC connectionreconfiguration complete message that is sent by the first UE to thefirst serving node after the first UE receives the RRC connectionreconfiguration message; and sending, by the first anchor node, a beareraddition/modification complete message to the first serving nodeaccording to the RRC connection reconfiguration complete message.

With reference to the first implementation manner of the seventh aspect,in an eighth implementation manner of the seventh aspect, the RRCmessage carried by the SRB1 is specifically an RRC connectionreconfiguration message or an RRC connection reconfiguration completemessage; and

the method further includes:

sending, by the first anchor node, the RRC connection reconfigurationmessage to the first serving node, where the RRC connectionreconfiguration message is the RRC connection reconfiguration messagethat is sent by the first anchor node to the first serving node afterthe first anchor node sends a bearer addition/modification requestmessage to the first serving node and receives a beareraddition/modification confirmation message sent by the first servingnode;

receiving, by the first anchor node, the RRC connection reconfigurationcomplete message sent by the first serving node, where the RRCconnection reconfiguration complete message is the RRC connectionreconfiguration complete message that is sent by the first UE and thatis received by the first serving node after the first serving nodereceives the RRC connection reconfiguration message sent by the firstanchor node and sends the RRC connection reconfiguration message to thefirst UE; and

sending, by the first anchor node, a bear addition/modification completemessage to the first serving node.

With reference to the first implementation manner of the seventh aspect,in a ninth implementation manner of the seventh aspect, the RRC messagecarried by the SRB1 is specifically an RRC connection reconfigurationmessage; and

the method further includes:

sending, by the first anchor node, the RRC connection reconfigurationmessage to the first serving node, so that the first serving node sendsthe RRC connection reconfiguration message to the first UE, where theRRC connection reconfiguration message is the RRC connectionreconfiguration message that is sent by the first anchor node after asecond anchor node or a neighboring base station receives a handoverrequest message sent by the first anchor node and sends a handoverrequest confirmation message to the first anchor node, and the firstserving node belongs to the first anchor node.

With reference to the first implementation manner of the seventh aspect,in a tenth implementation manner of the seventh aspect, the RRC messagefurther includes an RRC message carried by an SRB0, the RRC messagecarried by the SRB0 is specifically an RRC connection re-setup requestmessage or an RRC connection re-setup message, and the RRC messagecarried by the SRB1 is specifically an RRC connection re-setup completemessage; and

the method further includes:

receiving, by the first anchor node, the RRC connection re-setup requestmessage sent by the first serving node, where the RRC connectionre-setup request message is the RRC connection re-setup request messagethat is sent by the first UE to the first serving node after the firstUE finds a radio link failure RLF, receives a system message sent bymeans of broadcast by the first serving node, sends a random accessmessage to the first serving node according to the system message, andreceives a random access response message sent by the first servingnode;

sending, by the first anchor node, the RRC connection re-setup messageto the first serving node, so that the first serving node sends the RRCconnection re-setup message to the first UE; and

receiving, by the first anchor node, the RRC connection re-setupcomplete message sent by the first serving node, to set up an RRCconnection for the first anchor node and the first UE, where the RRCconnection re-setup complete message is the RRC connection re-setupcomplete message that is sent by the first UE and received by the firstserving node.

According to the RRC message processing method, apparatus, and systemprovided in the embodiments of the present invention, a first servingnode receives an RRC message sent by first UE or a first anchor node,and the RRC message includes an RRC message carried by an SRB1 and anRRC message carried by an SRB2. When the first serving node sends theRRC message to the first anchor node, a first PDCP layer of the firstanchor node processes the RRC message carried by the SRB1 and then sendsa processed message to an RRC layer entity, and a second PDCP layerprocesses the RRC message carried by the SRB2 and then sends a processedmessage to the RRC layer entity. Alternatively, a first RLC layer entityof the first serving node processes the RRC message carried by the SRB1and then sends a processed message to the first UE, and a second RLClayer entity of the first serving node processes the RRC message carriedby the SRB2 and then sends a processed message to the first UE. It maybe seen from above that in the embodiments of the present invention, thefirst serving node and the first anchor node are used to jointly processthe RRC message of the first UE, and different processing methods areused to process the RRC message according to different SRB types of theRRC message, so as to separate an RRC message processing function to twonodes, namely, the first serving node and the first anchor node. Becausean MME does not set up an S1 interface connection to the serving node,when the serving node handover is performed on the UE, an RRC connectionof the UE is maintained on the first anchor node, and an S1 connectionbetween the MME and the first anchor node does not change. Therefore,the handover process causes no handover signaling. In addition, when theMME has a paging message to be sent, the MME needs to send the pagingmessage only to all base stations in a TA area corresponding to thepaging message that have the S1 interface connection to the MME or thefirst anchor node that is in the TA area and has the S1 interfaceconnection to the MME. Because the MME does not set up the S1 interfaceconnection to the serving node, the MME does not need to send the pagingmessage to the serving node. Correspondingly, dense deployment ofserving nodes does not bring signaling increase, so as to effectivelyreduce signaling load of a core network.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic diagram of a network architecture according to anembodiment of the present invention;

FIG. 2 is a structural diagram of an RRC message processing systemaccording to an embodiment of the present invention;

FIG. 3 is a schematic structural diagram of an RRC message processingapparatus according to an embodiment of the present invention;

FIG. 4 is a schematic structural diagram of an RRC message processingapparatus according to an embodiment of the present invention;

FIG. 5 is a schematic structural diagram of a serving node according toan embodiment of the present invention;

FIG. 6 is a schematic structural diagram of an anchor node according toan embodiment of the present invention;

FIG. 7 is a flowchart of an RRC message processing method on a servingnode side according to an embodiment of the present invention;

FIG. 8 is a flowchart of an RRC message processing method on a servingnode side according to an embodiment of the present invention;

FIG. 9 is a flowchart of an RRC message processing method on a servingnode side according to an embodiment of the present invention;

FIG. 10 is a flowchart of an RRC message processing method on a servingnode side according to an embodiment of the present invention;

FIG. 11 is a flowchart of an RRC message processing method on a servingnode side according to an embodiment of the present invention;

FIG. 12 is a flowchart of an RRC message processing method on a servingnode side according to an embodiment of the present invention;

FIG. 13 is a flowchart of an RRC message processing method on an anchornode side according to an embodiment of the present invention;

FIG. 14 is a flowchart of an RRC message processing method on an anchornode side according to an embodiment of the present invention;

FIG. 15 is a flowchart of an RRC message processing method on an anchornode side according to an embodiment of the present invention;

FIG. 16 is a flowchart of an RRC message processing method on an anchornode side according to an embodiment of the present invention;

FIG. 17 is a flowchart of an RRC message processing method on an anchornode side according to an embodiment of the present invention; and

FIG. 18 is a flowchart of an RRC message processing method on an anchornode side according to an embodiment of the present invention.

DESCRIPTION OF EMBODIMENTS

The technical solutions of the present invention are further describedin detail with reference to accompanying drawings and embodiments asfollows:

To make the objectives, technical solutions, and advantages of theembodiments of the present invention clearer, the following clearly andcompletely describes the technical solutions in the embodiments of thepresent invention with reference to the accompanying drawings in theembodiments of the present invention. Apparently, the describedembodiments are some but not all of the embodiments of the presentinvention. All other embodiments obtained by a person of ordinary skillin the art based on the embodiments of the present invention withoutcreative efforts shall fall within the protection scope of the presentinvention.

To provide thorough understanding of the present invention, thefollowing further describes the embodiments of the present invention indetail with reference to the accompanying drawings. The foregoingembodiments are not intended to limit the protection scope of thepresent invention.

FIG. 1 is a schematic diagram of a network architecture according to anembodiment of the present invention. The network architecture includes amobility management entity (MME, Mobility management entity) 101, aserving gateway (SGW, Service Gateway) 102, an anchor node (Anchor node)103, a serving node (Serving node) 104, and user equipment (UE, UserEquipment) 105. The anchor node 103 may be an existing base station, ormay be a newly added network device. The serving node 104 may be anetwork device that provides a wireless communication service for the UE105, and may be specifically a base station that serves the UE 105. Inthe prior art, the serving node 104 directly sets up a connection to theMME 101. Different from that in the prior art, in the present invention,the serving node 104 does not directly set up a connection to the MME101; and instead, the serving node 104 sets up a connection to theanchor node 103, and the anchor node 103 sets up a connection to the MME101. Therefore, the serving node 104 sets up a connection to the MME 101by using the anchor node 103. In this embodiment of the presentinvention, an S1-C control plane interface and an S1-U user planeinterface are respectively established between the MME 101 in a corenetwork and the anchor node 103 and between the SGW 102 in the corenetwork and the anchor node 103. The anchor node 103 and the servingnode 104 are connected by using a signal tunnel (backhaul) to establishan interface. The interface may be specifically an enhanced X2interface, or may be an interface of another type. A radio linkconnection is set up between the UE 105 and the serving node 104.

In this embodiment of the present invention, the serving node 104 doesnot independently process RRC messages, but the anchor node 103 and theserving node 104 jointly process the RRC messages. That is, depending ontypes of the RRC messages, the anchor node 103 processes some RRCmessages, and the serving node 104 processes remaining RRC messages, sothat an RRC function is split onto the two nodes. Specifically, theanchor node 103 may include an RRC protocol entity used to process anRRC message carried by an SRB1 and an RRC protocol entity used toprocess an RRC message carried by an SRB2, a first Packet DataConvergence Protocol (PDCP, Packet Data Convergence Protocol) protocolentity used to process the RRC message carried by the SRB1, and a secondPDCP protocol entity used to process the RRC message carried by theSRB2. Therefore, the anchor node 103 has a function of processing theRRC message carried by the SRB1 and the RRC message carried by the SRB2.That is, after receiving the RRC message carried by the SRB1 and the RRCmessage carried by the SRB2 that are sent by the UE 105, the servingnode 104 forwards the RRC messages to the anchor node 103, and theanchor node 103 processes the received RRC message carried by the SRB1and the received RRC message carried by the SRB2. The serving node 104includes an RLC protocol entity used to process data carried by a dataradio bearer DRB, a Media Access Control MAC protocol entity used toprocess the RRC message carried by the SRB1, and a physical layer PHYprotocol entity used to process the RRC message carried by the SRB2, andan RRC protocol entity used to process an RRC message carried by anSRB0. The serving node 104 is configured to generate and send a commonRRC message, such as a MIB, a SIB, a paging message, or MBMS controlinformation. Therefore, the serving node 104 has a function ofprocessing the RRC message carried by the SRB0 and is responsible forprocessing a system broadcast message of a BCCH service, a cell pagingmessage of a PCCH service, and optionally, some RRC messages such as anRRC connection request message and an RRC connection setup message of aCCCH service in an RRC connection setup process and an RRC connectionre-setup process of UE.

The RRC message carried by the SRB1 may be specifically an RRC messagewhen connection setup is completed, and the RRC message carried by theSRB2 may be specifically an RRC message after connection setup iscompleted.

In addition, an RRC message processing procedure corresponding to thenetwork architecture may include a processing procedure of a first typeof RRC message, a processing procedure of a second type of RRC message,and a processing procedure of a third type of RRC message.

The processing procedure of the first type of RRC message is a processfor processing a dedicated downlink DL RRC message of UE. The DL RRCmessage includes the RRC message carried by the SRB1 and the RRC messagecarried by the SRB2. Specifically, after generating the RRC message thatis of the UE and carried by the SRB1 or the RRC message that is of theUE and carried by the SRB2, the RRC protocol entity of the anchor node103 delivers the RRC message, for processing, to the PDCP protocolentity corresponding to the SRB1 or corresponding to the SRB2. The PDCPprotocol entity of the anchor node forms a PDCP PDU, and sends the PDCPPDU to the serving node by using an interface between the anchor nodeand the serving node. After receiving the PDCP PDU, the serving nodeparses the PDCP PDU. Then, the RLC protocol entity that is of theserving node and corresponding to the SRB1 or the SRB2 processes thePDCP PDU. After the RLC protocol entity of the serving node processesthe PDCP PDU, the MAC layer and the PHY layer of the serving nodeprocess a processed PDCP PDU and then sends a processed PDCP PDU to theUE.

The processing procedure of the second type of RRC message is a processfor processing a dedicated uplink UL RRC message of UE. The UL RRCmessage includes the RRC message carried by the SRB1 and the RRC messagecarried by the SRB2. Specifically, after receiving the RRC message thatis of the UE and carried by the SRB1 or the RRC message that is of theUE and carried by the SRB2, the serving node delivers the RRC message,for processing, to the RLC protocol entity corresponding to the SRB1 orcorresponding to the SRB2. The RLC protocol entity of the serving nodeforms a PDCP PDU, and sends the PDCP PDU to the anchor node by using aninterface between the serving node and the anchor node. After receivingthe PDCP PDU, the anchor node parses the PDCP PDU. Then, the PDCPprotocol entity that is of the anchor node and corresponding to the SRB1or the SRB2 processes the PDCP PDU. The PDCP protocol entity processesthe RRC message and then sends a processed message to an RRC layerentity.

The processing procedure of the third type of RRC message is a processfor processing a common RRC message of UE. The common RRC messageincludes the RRC message carried by the SRB0. There are multiple typesof common RRC messages, for example, a system broadcast message of aBCCH service, a common cell DL RRC message (a paging message or abroadcast message) served by a PCCH, and the RRC message that is carriedby the SRB0 and served by a CCCH in connection setup and connectionre-setup processes. The RRC message carried by the SRB0 is processed bythe serving node.

The network architecture shown in FIG. 1 not only includes the servingnode 104, but also includes the anchor node 103. The anchor node 103 andthe serving node 104 jointly process an RRC message of the UE 105.Because the MME 101 does not set up an S1 interface connection to theserving node 104, when the serving node handover is performed on the UE105, an RRC connection of the UE is maintained on the anchor node 103,and an S1 connection between the MME 101 and the anchor node 103 doesnot change. Therefore, the handover process causes no correspondinghandover signaling. In addition, when the MME 101 has a to-be-sentpaging message, the MME 101 needs to send the paging message only to allbase stations in a TA area corresponding to the paging message that havethe S1 interface connection to the MME 101 or the anchor node 103 thatis in the TA area and has the S1 interface connection to the MME 101.Because the MME 101 does not set up the S1 interface connection to theserving node 104, the MME 101 does not need to send the paging messageto the serving node 104. Correspondingly, dense deployment of servingnodes 104 does not bring signaling increase, so as to effectively reducesignaling load of the core network.

FIG. 2 is a structural diagram of an RRC message processing systemaccording to an embodiment of the present invention. The system includesa first serving node 201, a first anchor node 202, and a mobilitymanagement entity MME 203. The first serving node 201 sets up aconnection to the first anchor node 202, and the first anchor node 202sets up a connection to the MME 203.

The first serving node 201 is configured to: receive a radio resourcecontrol RRC message sent by first user equipment UE, where the RRCmessage includes an RRC message carried by a signaling radio bearer SRB1or an RRC message carried by an SRB2; and send the RRC message to thefirst anchor node.

The first anchor node 202 is configured to: process, by using a firstPacket Data Convergence Protocol PDCP layer entity, the RRC messagecarried by the SRB1 and then send a processed message to an RRC layerentity; or process, by using a second PDCP layer entity, the RRC messagecarried by the SRB2 and then send a processed message to the RRC layerentity.

FIG. 3 is a schematic structural diagram of an RRC message processingapparatus according to an embodiment of the present invention. Theapparatus is disposed on a serving node. A first serving node sets up aconnection to a first anchor node. The first anchor node sets up aconnection to a mobility management entity MME.

The apparatus includes a receiving unit 301 and a sending unit 302.

The receiving unit 301 is configured to receive an RRC message sent byfirst user equipment UE. The RRC message includes an RRC message carriedby a signaling radio bearer SRB1 or an RRC message carried by an SRB2.

The sending unit 302 is configured to: send the RRC message received bythe receiving unit 301 to the first anchor node, so that a first PacketData Convergence Protocol PDCP layer entity of the first anchor nodeprocesses the RRC message carried by the SRB1 and then sends a processedmessage to an RRC layer entity of the first anchor node, or a secondPDCP layer entity of the first anchor node processes the RRC messagecarried by the SRB2 and then sends a processed message to an RRC layerentity of the first anchor node.

Preferably, the receiving unit 301 is further configured to receive anRRC message sent by the first anchor node. The RRC message includes anRRC message carried by an SRB1 or an RRC message carried by an SRB2. Theapparatus further includes a first processing unit 303 and a secondprocessing unit 304.

The first processing unit 303 is configured to process, by using a firstRadio Link Control RLC layer entity of the first serving node, the RRCmessage carried by the SRB1, so that the sending unit sends a processedmessage to the first UE.

The second processing unit 304 is configured to process, by using asecond RLC layer entity of the first serving node, the RRC messagecarried by the SRB2, so that the sending unit sends a processed messageto the first UE.

Preferably, the apparatus further includes a message generation unit.

The message generation unit is configured to generate, by using an RRClayer entity of the first serving node, an RRC message carried by anSRB0, so that the sending unit sends the RRC message carried by the SRB0to the first UE and/or the first anchor node.

Preferably, the RRC message further includes an RRC message carried byan SRB0. The sending unit 302 is further configured to send firstindication information to the first anchor node. The first indicationinformation is used by the first anchor node to identify, according tothe first indication information, that the RRC message is the RRCmessage carried by the SRB0, and to perform processing by using the RRClayer entity of the first anchor node. The receiving unit 301 is furtherconfigured to receive first indication information sent by the firstanchor node. The first indication information is used by the firstserving node to identify, according to the first indication information,that the RRC message is the RRC message carried by the SRB0, and toperform processing by using an RRC layer entity of the first servingnode.

Preferably, the sending unit 302 is further configured to send secondindication information to the first anchor node. The second indicationinformation is used by the first anchor node to identify, according tothe second indication information, that the RRC message is the RRCmessage carried by the SRB1. The receiving unit 301 is furtherconfigured to receive second indication information sent by the firstanchor node. The second indication information is used by the firstserving node to identify, according to the second indicationinformation, that the RRC message is the RRC message carried by theSRB1.

Preferably, the sending unit 302 is further configured to send thirdindication information to the first anchor node. The third indicationinformation is used by the first anchor node to identify, according tothe third indication information, that the RRC message is the RRCmessage carried by the SRB2. The receiving unit 301 is furtherconfigured to receive third indication information sent by the firstanchor node. The third indication information is used by the firstserving node to identify, according to the third indication information,that the RRC message is the RRC message carried by the SRB2.

Preferably, the apparatus further includes: a first processing unit 303,configured to: before the sending unit 302 sends the RRC message to thefirst anchor node, process, by using a first RLC layer entity of thefirst serving node, the RRC message carried by the SRB1: and

a second processing unit 304, configured to: before the sending unit 302sends the RRC message to the first anchor node, process, by using asecond RLC layer entity of the first serving node, the RRC messagecarried by the SRB2.

Preferably, the sending unit 302 is specifically configured to: send theRRC message processed by the first processing unit 303 to the first UEby using a Media Access Control MAC layer and a physical layer, or sendthe RRC message processed by the second processing unit to the first UEby using a MAC layer and a physical layer.

Preferably, the sending unit 302 is specifically configured to: send theRRC message processed by the first processing unit 303 to the first UE,so that a first PDCP layer entity of the first UE processes the RRCmessage carried by the SRB1 and then sends the processed message to anRRC layer entity; or send the RRC message processed by the secondprocessing unit 304 to the first UE, so that a second PDCP layer entityof the first UE processes the RRC message carried by the SRB2 and thensends the processed message to the RRC layer entity.

Preferably, the RRC message further includes an RRC message carried byan SRB0. The RRC message carried by the SRB0 is specifically an RRCconnection request message or an RRC connection setup message. The RRCmessage carried by the SRB1 is specifically an RRC connection setupcomplete message.

The receiving unit 301 is specifically configured to receive the RRCconnection request message sent by the first UE. The RRC connectionrequest message is an RRC connection request message that is sent by thefirst UE to the first serving node after the first UE receives a systemmessage sent by means of broadcast by the first serving node, sends arandom access message to the first serving node according to the systemmessage, and receives a random access response message sent by the firstserving node.

The sending unit 302 is specifically configured to forward the RRCconnection request message received by the receiving unit to the firstanchor node.

The receiving unit 301 is further configured to receive the RRCconnection setup message sent by the first anchor node. The RRCconnection setup message is the RRC connection setup message generatedby the first anchor node according to the received RRC connectionrequest message.

The sending unit 302 is further configured to send the RRC connectionsetup message received by the receiving unit 301 to the first UE.

The receiving unit 301 is further configured to receive the RRCconnection setup complete message sent by the first UE.

The sending unit 302 is further configured to send the RRC connectionsetup complete message received by the receiving unit 301 to the firstanchor node, to set up an RRC connection for the first anchor node andthe first UE.

Preferably, the RRC message carried by the SRB1 is specifically an RRCconnection reconfiguration message or an RRC connection reconfigurationcomplete message.

The sending unit 302 is specifically configured to send a beareraddition/modification confirmation message to the first anchor node. Thebearer addition/modification confirmation message is the beareraddition/modification confirmation message that is generated by thefirst serving node according to a bearer addition/modification requestmessage after the first serving node receives the beareraddition/modification request message sent by the first anchor node.

The receiving unit 301 is specifically configured to receive the RRCconnection reconfiguration message sent by the first anchor node.

The sending unit 302 is further configured to send the RRC connectionreconfiguration message received by the receiving unit 301 to the firstUE.

The receiving unit 301 is further configured to receive the RRCconnection reconfiguration complete message sent by the first UE.

The sending unit 302 is further configured to send the RRC connectionreconfiguration complete message received by the receiving unit 301 tothe first anchor node, so that the first anchor node sends a beareraddition/modification complete message to the first serving nodeaccording to the RRC connection reconfiguration complete message.

Preferably, the RRC message carried by the SRB1 is specifically an RRCconnection reconfiguration message or an RRC connection reconfigurationcomplete message.

The receiving unit 301 is specifically configured to receive the RRCconnection reconfiguration message sent by the first anchor node. TheRRC connection reconfiguration message is the RRC connectionreconfiguration message that is sent by the first anchor node after thefirst serving node receives a bearer addition/modification requestmessage sent by the first anchor node and sends a beareraddition/modification confirmation message to the first anchor node.

The sending unit 302 is specifically configured to send the RRCconnection reconfiguration message received by the receiving unit 301 tothe first UE.

The receiving unit 301 is further configured to receive the RRCconnection reconfiguration complete message sent by the first UE.

The sending unit 302 is further configured to send the RRC connectionreconfiguration complete message received by the receiving unit 301 tothe first anchor node.

The receiving unit 301 is further configured to receive a bearaddition/modification complete message sent by the first anchor node.

Preferably, the RRC message carried by the SRB1 is specifically an RRCconnection reconfiguration message.

The receiving unit 301 is specifically configured to receive the RRCconnection reconfiguration message sent by the first anchor node. TheRRC connection reconfiguration message is the RRC connectionreconfiguration message that is sent by the first anchor node after asecond anchor node or a neighboring base station receives a handoverrequest message sent by the first anchor node and sends a handoverrequest confirmation message to the first anchor node. The first servingnode belongs to the first anchor node.

The sending unit 302 is specifically configured to send the RRCconnection reconfiguration message received by the receiving unit 301 tothe first UE.

Preferably, the RRC message further includes an RRC message carried byan SRB0. The RRC message carried by the SRB0 is specifically an RRCconnection re-setup request message or an RRC connection re-setupmessage. The RRC message carried by the SRB1 is specifically an RRCconnection re-setup complete message.

The receiving unit 301 is specifically configured to receive the RRCconnection re-setup request message sent by the first UE. The RRCconnection re-setup request message is the RRC connection re-setuprequest message that is sent by the first UE after the first UE finds aradio link failure RLF, receives a system message sent by means ofbroadcast by the first serving node, sends a random access message tothe first serving node according to the system message, and receives arandom access response message sent by the first serving node.

The sending unit 302 is specifically configured to send the RRCconnection re-setup request message received by the receiving unit 301to the first anchor node.

The receiving unit 301 is further configured to receive the RRCconnection re-setup message sent by the first anchor node.

The sending unit 302 is further configured to send the RRC connectionre-setup message received by the receiving unit 301 to the first UE.

The receiving unit 301 is further configured to receive the RRCconnection re-setup complete message sent by the first UE.

The sending unit 302 is further configured to send the RRC connectionre-setup complete message received by the receiving unit 301 to thefirst anchor node, to set up an RRC connection for the first anchor nodeand the first UE.

FIG. 4 is a schematic structural diagram of an RRC message processingapparatus according to an embodiment of the present invention. Theapparatus is disposed on an anchor node. A first serving node sets up aconnection to a first anchor node. The first anchor node sets up aconnection to a mobility management entity MME. The apparatus includes asending unit 401.

The sending unit 401 is configured to send a radio resource control RRCmessage to the first serving node. The RRC message includes an RRCmessage carried by a signaling radio bearer SRB1 or an RRC messagecarried by an SRB2.

Preferably, the apparatus further includes a receiving unit 402, a firstpacket data processing unit 403, a second packet data processing unit404.

The receiving unit 402 is configured to receive an RRC message sent bythe first serving node.

The first packet data processing unit 403 is configured to process, byusing a first Packet Data Convergence Protocol PDCP layer entity of thefirst anchor node, an RRC message that is carried by an SRB1 andreceived by the receiving unit 402 and then send a processed message toan RRC layer entity of the first anchor node.

The second packet data processing unit 404 is configured to process, byusing a second PDCP layer entity of the first anchor node, an RRCmessage that is carried by an SRB2 and received by the receiving unit402 and then send a processed message to the RRC layer entity of thefirst anchor node.

Preferably, the apparatus further includes a first message generationunit.

The first message generation unit is configured to generate, by usingthe RRC layer entity of the first anchor node, the RRC message carriedby the SRB1 or the RRC message carried by the SRB2.

The sending unit is specifically configured to send, to the firstserving node, the RRC message that is carried by the SRB1 and generatedby the first message generation unit or the RRC message that is carriedby the SRB2 and generated by the first message generation unit.

Preferably, the RRC message further includes an RRC message carried byan SRB0. The receiving unit 402 is further configured to receive firstindication information sent by the first serving node.

The apparatus further includes an identification unit.

The identification unit is configured to: identify, according to thefirst indication information received by the receiving unit 402, thatthe RRC message is the RRC message carried by the SRB0, and performprocessing by using the RRC layer entity of the first anchor node.

The sending unit 401 is further configured to send first indicationinformation to the first serving node. The first indication informationis used by the first serving node to identify, according to the firstindication information, that the RRC message is the RRC message carriedby the SRB0, and to perform processing by using an RRC layer entity ofthe first serving node.

Preferably, the receiving unit 402 is further configured to receivesecond indication information sent by the first serving node.

The apparatus further includes an identification unit.

The identification unit is configured to identify, according to thesecond indication information received by the receiving unit 402, thatthe RRC message is the RRC message carried by the SRB1.

The sending unit 401 is further configured to send second indicationinformation to the first serving node. The second indication informationis used by the first serving node to identify, according to the secondindication information, that the RRC message is the RRC message carriedby the SRB1.

Preferably, the receiving unit 402 is further configured to receivethird indication information sent by the first serving node.

The apparatus further includes an identification unit.

The identification unit is configured to identify, according to thethird indication information received by the receiving unit, that theRRC message is the RRC message carried by the SRB2.

The sending unit is further configured to send third indicationinformation to the first serving node. The third indication informationis used by the first serving node to identify, according to the thirdindication information, that the RRC message is the RRC message carriedby the SRB2.

Preferably, the RRC message further includes an RRC message carried byan SRB0. The RRC message carried by the SRB0 is specifically an RRCconnection request message or an RRC connection setup message. The RRCmessage carried by the SRB1 is specifically an RRC connection setupcomplete message.

The receiving unit 402 is specifically configured to receive the RRCconnection request message forwarded by the first serving node. The RRCconnection request message is an RRC connection request message that issent by the first UE to the first serving node after the first UEreceives a system message sent by means of broadcast by the firstserving node, sends a random access message to the first serving nodeaccording to the system message, and receives a random access responsemessage sent by the first serving node.

The apparatus further includes a second message generation unit.

The second message generation unit is configured to generate the RRCconnection setup message according to the RRC connection request messagereceived by the receiving unit.

The sending unit 401 is specifically configured to send, to the firstserving node, the RRC connection setup message generated by the secondmessage generation unit, so that the first serving node sends the RRCconnection setup message to the first UE.

The receiving unit 402 is further configured to receive the RRCconnection setup complete message sent by the first serving node, to setup an RRC connection for the first anchor node and the first UE. The RRCconnection setup complete message is an RRC connection setup completemessage that is sent by the first UE to the first serving node after thefirst UE receives the RRC connection setup message.

Preferably, the RRC message carried by the SRB1 is specifically an RRCconnection reconfiguration message or an RRC connection reconfigurationcomplete message.

The receiving unit 402 is specifically configured to receive a beareraddition/modification confirmation message sent by the first servingnode. The bearer addition/modification confirmation message is thebearer addition/modification confirmation message that is generated bythe first serving node according to a bearer addition/modificationrequest message after the first anchor node sends the beareraddition/modification request message to the first serving node.

The sending unit 401 is specifically configured to send the RRCconnection reconfiguration message to the first serving node, so thatthe first serving node sends the RRC connection reconfiguration messageto the first UE.

The receiving unit 402 is further configured to receive the RRCconnection reconfiguration complete message sent by the first servingnode. The RRC connection reconfiguration complete message is the RRCconnection reconfiguration complete message that is sent by the first UEto the first serving node after the first UE receives the RRC connectionreconfiguration message. The first anchor node sends a beareraddition/modification complete message to the first serving nodeaccording to the RRC connection reconfiguration complete message.

Preferably, the RRC message carried by the SRB1 is specifically an RRCconnection reconfiguration message or an RRC connection reconfigurationcomplete message.

The sending unit 401 is specifically configured to send the RRCconnection reconfiguration message to the first serving node. The RRCconnection reconfiguration message is the RRC connection reconfigurationmessage that is sent by the first anchor node to the first serving nodeafter the first anchor node sends a bearer addition/modification requestmessage to the first serving node and receives a beareraddition/modification confirmation message sent by the first servingnode.

The receiving unit 402 is specifically configured to receive the RRCconnection reconfiguration complete message sent by the first servingnode. The RRC connection reconfiguration complete message is the RRCconnection reconfiguration complete message that is sent by the first UEand that is received by the first serving node after the first servingnode receives the RRC connection reconfiguration message sent by thefirst anchor node and sends the RRC connection reconfiguration messageto the first UE.

The sending unit 401 is further configured to send a bearaddition/modification complete message to the first serving node.

Preferably, the RRC message carried by the SRB1 is specifically an RRCconnection reconfiguration message.

The sending unit 401 is specifically configured to send the RRCconnection reconfiguration message to the first serving node, so thatthe first serving node sends the RRC connection reconfiguration messageto the first UE. The RRC connection reconfiguration message is the RRCconnection reconfiguration message that is sent by the first anchor nodeafter a second anchor node or a neighboring base station receives ahandover request message sent by the first anchor node and sends ahandover request confirmation message to the first anchor node. Thefirst serving node belongs to the first anchor node.

Preferably, the RRC message further includes an RRC message carried byan SRB0. The RRC message carried by the SRB0 is specifically an RRCconnection re-setup request message or an RRC connection re-setupmessage. The RRC message carried by the SRB1 is specifically an RRCconnection re-setup complete message.

The receiving unit 402 is specifically configured to receive the RRCconnection re-setup request message sent by the first serving node. TheRRC connection re-setup request message is the RRC connection re-setuprequest message that is sent by the first UE to the first serving nodeafter the first UE finds a radio link failure RLF, receives a systemmessage sent by means of broadcast by the first serving node, sends arandom access message to the first serving node according to the systemmessage, and receives a random access response message sent by the firstserving node.

The sending unit 401 is specifically configured to send the RRCconnection re-setup message to the first serving node, so that the firstserving node sends the RRC connection re-setup message to the first UE.

The receiving unit 402 is further configured to receive the RRCconnection re-setup complete message sent by the first serving node, toset up an RRC connection for the first anchor node and the first UE. TheRRC connection re-setup complete message is the RRC connection re-setupcomplete message that is sent by the first UE and received by the firstserving node.

FIG. 5 is a schematic structural diagram of a serving node according toan embodiment of the present invention. The serving node sets up aconnection to a first anchor node. The first anchor node sets up aconnection to a mobility management entity MME.

The serving node includes a transmitter 501 and a receiver 502.

The receiver 502 is configured to receive a radio resource control RRCmessage sent by first user equipment UE. The RRC message includes an RRCmessage carried by a signaling radio bearer SRB1 or an RRC messagecarried by an SRB2.

The transmitter 501 is configured to: send the RRC message received bythe receiver 502 to the first anchor node, so that a first Packet DataConvergence Protocol PDCP layer entity of the first anchor nodeprocesses the RRC message carried by the SRB1 and then sends a processedmessage to an RRC layer entity of the first anchor node, or a secondPDCP layer entity of the first anchor node processes the RRC messagecarried by the SRB2 and then sends a processed message to an RRC layerentity of the first anchor node.

FIG. 6 is a schematic structural diagram of an anchor node according toan embodiment of the present invention. A first serving node sets up aconnection to the anchor node. The anchor node sets up a connection to amobility management entity MME. The anchor includes a transmitter 601.

The transmitter 601 is configured to send a radio resource control RRCmessage to the first serving node. The RRC message includes an RRCmessage carried by a signaling radio bearer SRB1 or an RRC messagecarried by an SRB2.

FIG. 7 is a flowchart of an RRC message processing method on a servingnode side according to an embodiment of the present invention. The RRCmessage processing method is based on the network architecture shown inFIG. 1 . The method is executed by a serving node. A first serving nodesets up a connection to a first anchor node. The first anchor node setsup a connection to a mobility management entity MME. As shown in FIG. 7, the method specifically includes the following steps.

Step 701. The first serving node receives an RRC message sent by firstUE, where the RRC message includes an RRC message carried by a signalingradio bearer SRB1 or an RRC message carried by an SRB2.

Because there are multiple UEs in a network, to distinguish between themultiple UEs, current UE is referred to as the first UE. In addition,there may also be multiple serving nodes and anchor nodes. A servingnode handover may be performed on UE, that is, handing over from aserving node to another serving node. An anchor node handover may alsobe performed on the UE, that is, handing over from an anchor node toanother anchor node. Therefore, a current serving node of the first UEis referred to as the first serving node, and a current anchor node ofthe first UE is referred to as the first anchor node.

An RRC message sent by the first UE or the first anchor node is not amessage obtained after processing by an RRC layer entity but onlycontent that includes an RRC PDU, for example, a PDCP PDU that is sentby the first UE or the first anchor node and that includes the RRCmessage carried by the SRB1 or the RRC message carried by the SRB2, oran RLC PDU that is sent by the first UE or the first anchor node andthat includes an RRC message carried by an SRB0. When the RRC message istransmitted between the first serving node and the first anchor node,the PDCP PDU or the RLC PDU may also be used as an information unit andbe included in another protocol message, for example, included incontrol plane interface signaling.

In this embodiment of the present invention, the first serving node mayhave an RRC function corresponding to an SRB0. The method may furtherinclude: generating, by an RRC layer entity of the first serving node,an RRC message carried by an SRB0, and sending the RRC message carriedby the SRB0 to the first UE and/or the first anchor node.

The RRC function corresponding to the SRB0 may specifically include asystem broadcast function, a paging function, some RRC connection setupfunctions, or some RRC connection re-setup functions. The some functionsspecifically refer to processing an RRC connection setup requestmessage, generating and delivering an RRC connection setup message,processing an RRC connection re-setup request message, or generating anddelivering an RRC connection re-setup message.

Step 702: The first serving node sends the RRC message to the firstanchor node, so that a first PDCP layer entity of the first anchor nodeprocesses the RRC message carried by the SRB1 and then sends a processedmessage to an RRC layer entity of the first anchor node, or a secondPDCP layer entity of the first anchor node processes the RRC messagecarried by the SRB2 and then sends a processed message to an RRC layerentity of the first anchor node.

In this embodiment of the present invention, the method may furtherinclude: receiving, by the first serving node, an RRC message sent bythe first anchor node, where the RRC message includes an RRC messagecarried by an SRB1 or an RRC message carried by an SRB2; and processing,by a first Radio Link Control RLC layer entity of the first servingnode, the RRC message carried by the SRB1 and then sending a processedmessage to the first UE: or processing, by a second RLC layer entity ofthe first serving node, the RRC message carried by the SRB2 and thensending a processed message to the first UE.

Inter-device control plane interface signaling is used between theserving node and the anchor node. Therefore, in order that the servingnode and the anchor node can distinguish an SRB type of a received RRCmessage, a transmitter may send indication information to a receiver,and indicate the SRB type of the RRC message to the receiver by usingthe indication information, for example, indicate whether the RRCmessage is specifically an RRC message carried by the SRB1 or an RRCmessage carried by the SRB2. In this embodiment of the presentinvention, the indication information may be carried when the RRCmessage is being sent. Specifically, the indication information may becarried in the RRC message, or the indication information may be carriedin a control plane signaling message that carries the RRC message; orthe indication information may be sent independently after the RRCmessage is sent.

In this embodiment of the present invention, that the first PDCP layerentity of the first anchor node processes the RRC message carried by theSRB1 and then sends the processed message to the RRC layer entityspecifically includes: The first PDCP layer entity of the first anchornode processes the RRC message carried by the SRB1, to obtain a PDCP PDUthat includes the RRC message carried by the SRB1; and sends, to the RRClayer entity, the PDCP PDU that includes the RRC message carried by theSRB1. The PDCP PDU may be used as an information unit and be included inanother protocol message, for example, included in control planeinterface signaling.

In addition, the RRC message may further include an RRC message carriedby an SRB0. When the RRC message sent by the first serving node to thefirst anchor node is specifically the RRC message carried by the SRB0,the method may further include: sending, by the first serving node,first indication information to the first anchor node, where the firstindication information is used by the first anchor node to identify,according to the first indication information, that the RRC message isthe RRC message carried by the SRB0, and to perform processing by usingthe RRC layer entity of the first anchor node: or receiving, by thefirst serving node, first indication information sent by the firstanchor node, where the first indication information is used by the firstserving node to identify, according to the first indication information,that the RRC message is the RRC message carried by the SRB0, and toperform processing by using an RRC layer entity of the first servingnode.

Similarly, the first serving node may further send second indicationinformation to the first anchor node. The second indication informationis used by the first anchor node to identify, according to the secondindication information, that the RRC message is the RRC message carriedby the SRB1. Alternatively, the first serving node receives secondindication information sent by the first anchor node. The secondindication information is used by the first serving node to identify,according to the second indication information, that the RRC message isthe RRC message carried by the SRB1.

Similarly, the first serving node may further send third indicationinformation to the first anchor node. The third indication informationis used by the first anchor node to identify, according to the thirdindication information, that the RRC message is the RRC message carriedby the SRB2. Alternatively, the first serving node receives thirdindication information sent by the first anchor node. The thirdindication information is used by the first serving node to identify,according to the third indication information, that the RRC message isthe RRC message carried by the SRB2.

In this embodiment of the present invention, before the first servingnode sends the RRC message to the first anchor node, the method mayfurther include: processing, by the first RLC layer entity of the firstserving node, the RRC message carried by the SRB1; or processing, by thesecond RLC layer entity, the RRC message carried by the SRB2.Specifically, the first RLC layer entity of the first serving nodeprocesses the RRC message carried by the SRB1 to obtain an RLC PDU thatincludes the RRC message carried by the SRB1, or the second RLC layerentity of the first serving node processes the RRC message carried bythe SRB2 to obtain an RLC PDU that includes the RRC message carried bythe SRB2. The RLC PDU may be used as an information unit and be includedin another protocol message, for example, included in control planeinterface signaling.

In addition, the processing, by a first RLC layer entity of the firstserving node, the RRC message carried by the SRB1 and then sending aprocessed message to the first UE; or processing, by a second RLC layerentity of the first serving node, the RRC message carried by the SRB2and then sending a processed message to the first UE may specificallyinclude: processing, by the first RLC layer entity of the first servingnode, the RRC message carried by the SRB1 and then sending the processedmessage to the first UE by using a Media Access Control MAC layer and aphysical layer: or processing, by the second RLC layer entity of thefirst serving node, the RRC message carried by the SRB2 and then sendingthe processed message to the first UE by using a MAC layer and aphysical layer.

Alternatively, the processing, by a first RLC layer entity of the firstserving node, the RRC message carried by the SRB1 and then sending aprocessed message to the first UE; or processing, by a second RLC layerentity of the first serving node, the RRC message carried by the SRB2and then sending a processed message to the first UE may specificallyinclude: processing, by the first RLC layer entity of the first servingnode, the RRC message carried by the SRB1 and then sending the processedmessage to the first UE, so that a first PDCP layer entity of the firstUE processes the RRC message carried by the SRB1 and then sends theprocessed message to an RRC layer entity; or processing, by the secondRLC layer entity of the first serving node, the RRC message carried bythe SRB2 and then sending the processed message to the first UE, so thata second PDCP layer entity of the first UE processes the RRC messagecarried by the SRB2 and then sends the processed message to the RRClayer entity.

It may be learned from the foregoing processing process that, in the RRCmessage processing method provided in this embodiment of the presentinvention, an RRC message cannot be directly sent between first UE and afirst anchor node, and needs to be forwarded by a first serving node.That is, when the first UE needs to send an RRC message to the firstanchor node, the first UE first needs to send the RRC message to thefirst serving node, and then the first serving node sends the RRCmessage to the first anchor node. When the first anchor node needs tosend an RRC message to the first UE, the first anchor node first needsto send the RRC message to the first serving node, and then the firstserving node sends the RRC message to the first UE. Because the RRCmessage needs to pass through two nodes, namely, the first anchor nodeand the first serving node, an RRC function can be separated to the twonodes by using the method provided in this embodiment of the presentinvention.

FIG. 8 is a flowchart of an RRC message processing method on a servingnode side according to an embodiment of the present invention. The RRCmessage processing method is based on the network architecture shown inFIG. 1 , and is specifically used to set up an RRC connection. Themethod is executed by a serving node. An RRC message includes an RRCmessage carried by an SRB1, an RRC message carried by an SRB2, and anRRC message carried by an SRB0. The RRC message carried by the SRB0 isspecifically an RRC connection request message or an RRC connectionsetup message, and the RRC message carried by the SRB1 is specificallyan RRC connection setup complete message. As shown in FIG. 8 , themethod specifically includes the following steps.

Step 801: A first serving node receives an RRC connection requestmessage sent by first UE, where the RRC connection request message is anRRC connection request message that is sent by the first UE to the firstserving node after the first UE receives a system message sent by meansof broadcast by the first serving node, sends a random access message tothe first serving node according to the system message, and receives arandom access response message sent by the first serving node.

The first serving node may allocate a cell radio network temporaryidentifier CRNTI to the UE, and adds the CRNTI to the random accessresponse message, to send the random access response message to thefirst UE.

Step 802: The first serving node forwards the RRC connection requestmessage to a first anchor node.

In this embodiment of the present invention, the first serving node maysend first indication information when forwarding the RRC connectionrequest message to the first anchor node. The first indicationinformation is used to indicate that the RRC connection request messageis an RRC message carried by the SRB0. The first indication informationmay be an explicit signaling indication or a particular message name.The latter is, for example, SRB0RRCTransfer or InitialRRCTransfer.Therefore, after identifying, according to the first indicationinformation, that the RRC connection request message is the RRC messagecarried by the SRB0, the first anchor node directly delivers the messageto an RRC layer entity for processing.

Optionally, when forwarding the RRC connection request message to thefirst anchor node, the first serving node may add a CRNTI and/or an X2APID of the UE to the RRC connection request message. The CRNTI is carriedfor subsequent potential MRO optimization. For example, if a CRNTI in anRLF indication received from a neighboring cell is the same as theCRNTI, it may be determined that an RLF occurs in the UE, and the firstanchor node may create UE context and an RRC connection for the UEaccording to the information.

Step 803: The first serving node receives an RRC connection setupmessage sent by the first anchor node, where the RRC connection setupmessage is the RRC connection setup message generated by the firstanchor node according to the received RRC connection request message.

In this embodiment of the present invention, the first anchor node mayadd the first indication information to a message when sending the RRCconnection setup message, and specifically, may add the first indicationinformation to the RRC connection setup message or add the firstindication information to a control plane signaling message that carriesthe RRC connection setup message. Alternatively, the first anchor nodemay independently send the first indication information after sendingthe RRC connection setup message, so that the first serving nodeidentifies, according to the first indication information, that the RRCconnection setup message is the RRC message carried by the SRB0.

Step 804: The first serving node sends the RRC connection setup messageto the first UE.

Step 805: The first serving node receives an RRC connection setupcomplete message sent by the first UE.

In this embodiment of the present invention, the first serving node hasa first RLC layer entity used to process an RRC message carried by theSRB1 and a second RLC layer entity used to process an RRC messagecarried by the SRB2. Because the RRC connection setup complete messageis the RRC message carried by the SRB1, the first RLC layer entity ofthe first serving node processes the RRC connection setup completemessage and then sends a processed message to the first UE.

Step 806: The first serving node sends the RRC connection setup completemessage to the first anchor node, to set up an RRC connection for thefirst anchor node and the first UE.

The first serving node may add second indication information to amessage when sending the RRC connection setup complete message to thefirst anchor node, and specifically, may add the second indicationinformation to the RRC connection setup complete message or add thesecond indication information to a control plane signaling message thatcarries the RRC connection setup complete message. Alternatively, thefirst serving node may independently send the second indicationinformation after sending the RRC connection setup complete message, sothat the first anchor node identifies, according to the secondindication information, that the RRC connection setup complete messageis the RRC message carried by the SRB1. Then, the RRC connection setupcomplete message is processed at a first PDCP layer of the first anchornode, and then a processed message is sent to the RRC layer entity.

In addition, after the RRC connection is set up between the first anchornode and the first UE, in a subsequent uplink/downlink RRC messageprocessing process, the first serving node may forward, to the firstanchor node, a PDCP PDU corresponding to an RRC message that is carriedby the SRB1 and received from the first UE and a PDCP PDU correspondingto an RRC message that is carried by the SRB2 and received from thefirst UE. After a PDCP entity of the SRB1 and a PDCP entity of the SRB2respectively process the RRC messages, the first anchor node may deliverprocessed messages to the RRC layer entity. In addition, the firstserving node delivers, respectively to an RLC entity of the SRB1 and anRLC entity of the SRB2 for processing, a PDCP PDU corresponding to anRRC message that is carried by the SRB1 and received from the firstanchor node and a PDCP PDU corresponding to an RRC message that iscarried by the SRB2 and received from the first anchor node, and thensends processed messages to the first UE by using a MAC layer and aphysical layer. Each time an RRC message is sent between the firstanchor node and the first serving node, whether the RRC message is anRRC message carried by an SRB0, an RRC message carried by an SRB1, or anRRC message carried by an SRB2 needs to be indicated, so that a receiverperforms processing.

It may be learned from the foregoing processing process that, in the RRCmessage processing method provided in this embodiment of the presentinvention, an RRC connection may be set up for a first anchor node andfirst UE. In addition, in a process of setting up the RRC connection,for an RRC message between a first serving node and the first anchornode, indication information used to indicate an SRB type may be carriedwhen the RRC message is being sent, or the indication information may beindependently sent, so that the first serving node and the first anchornode perform corresponding processing. Therefore, an RRC function isseparated to two nodes, namely, the first serving node and the firstanchor node.

FIG. 9 is a flowchart of an RRC message processing method on a servingnode side according to an embodiment of the present invention. The RRCmessage processing method is based on the network architecture shown inFIG. 1 , and is specifically used to set up a DRB bearer. The method isexecuted by a serving node. The RRC message includes an RRC messagecarried by an SRB1. The RRC message carried by the SRB1 is specificallyan RRC connection reconfiguration message or an RRC connectionreconfiguration complete message. As shown in FIG. 9 , the methodspecifically includes the following steps.

Step 901: A first serving node sends a bearer addition/modificationconfirmation message to a first anchor node, where the beareraddition/modification confirmation message is the beareraddition/modification confirmation message that is generated by thefirst serving node according to a bearer addition/modification requestmessage after the first serving node receives the beareraddition/modification request message sent by the first anchor node.

In this embodiment of the present invention, after receiving an RRCconnection setup complete message sent by first UE, the first anchornode may send initial UE information to an MME, receive an initialenvironment setup request message or an E-RAB setup request message thatis sent by the MME, and send the bearer addition/modification requestmessage to the first serving node.

E-RAB is short for E-UTRAN radio access bearer, E-UTRAN is short forevolved UTRAN, UTRAN is short for UMTS Terrestrial Radio Access Network,and RAB is short for radio access bearer, radio access bearer.

Step 902: The first serving node receives an RRC connectionreconfiguration message sent by the first anchor node.

The first serving node may further receive second indicationinformation, so that the first serving node identifies, according to thesecond indication information, that the RRC connection reconfigurationmessage is an RRC message carried by an SRB1. A first RLC layer entityof the first serving node processes the RRC message carried by the SRB1.

Step 903: Send the RRC connection reconfiguration message to first UE.

In this embodiment of the present invention, specifically, the first RLClayer entity of the first serving node may process the RRC messagecarried by the SRB1 and then send a processed message to the first UE byusing a MAC layer and a physical layer.

Step 904: Receive the RRC connection reconfiguration complete messagesent by the first UE.

Step 905. Send the RRC connection reconfiguration complete message tothe first anchor node, so that the first anchor node sends a beareraddition/modification complete message to the first serving nodeaccording to the RRC connection reconfiguration complete message.

The second indication information may be carried when the RRC connectionreconfiguration complete message is being sent. Specifically, the secondindication information may be carried in the RRC connectionreconfiguration complete message, or the second indication informationmay be carried in a control plane signaling message that carries the RRCconnection reconfiguration complete message. Alternatively, the secondindication information may be independently sent after the RRCconnection reconfiguration complete message is sent, so that the firstanchor node identifies, according to the second indication information,that the RRC connection reconfiguration message is the RRC messagecarried by the SRB1. A first PDCP layer entity of the first anchor nodeprocesses the RRC message carried by the SRB1 and then sends a processedmessage to an RRC layer entity. Preferably, the second indicationinformation is carried in the control plane signaling message.

It may be learned from the foregoing processing process that, in the RRCmessage processing method provided in this embodiment of the presentinvention, a DRB bearer may be set up. In addition, in a process ofsetting up the DRB bearer, for an RRC message between a first servingnode and a first anchor node, indication information used to indicate anSRB type may be carried when the RRC message is being sent, or theindication information may be independently sent, so that the firstserving node and the first anchor node perform corresponding processing.Therefore, an RRC function is separated to two nodes, namely, the firstserving node and the first anchor node.

FIG. 10 is a flowchart of an RRC message processing method on a servingnode side according to an embodiment of the present invention. The RRCmessage processing method is based on the network architecture shown inFIG. 1 , and is specifically used for handover between serving nodesconnected to an anchor node. The method is executed by a serving node.The RRC message includes an RRC message carried by an SRB1. The RRCmessage carried by the SRB1 is specifically an RRC connectionreconfiguration message or an RRC connection reconfiguration completemessage. As shown in FIG. 10 , the method specifically includes thefollowing steps.

Step 1001: A first serving node receives an RRC connectionreconfiguration message sent by a first anchor node, where the RRCconnection reconfiguration message is the RRC connection reconfigurationmessage that is sent by the first anchor node after the first servingnode receives a bearer addition/modification request message sent by thefirst anchor node and sends a bearer addition/modification confirmationmessage to the first anchor node.

Second indication information may be carried when the RRC connectionreconfiguration message is being sent. Specifically, the secondindication information may be carried in the RRC connectionreconfiguration message, or the second indication information may becarried in a control plane signaling message that carries the RRCconnection reconfiguration message. Alternatively, the second indicationinformation may be independently sent after the RRC connectionreconfiguration message is sent, so that the first serving nodeidentifies, according to the second indication information, that the RRCconnection reconfiguration message is an RRC message carried by an SRB1.A first RLC layer entity of the first serving node processes the RRCmessage carried by the SRB1.

In this embodiment of the present invention, the first anchor node maysend a bearer release request message to a second serving node beforethe first anchor node sends the RRC connection reconfiguration messageto the first serving node. Alternatively, the first anchor node may senda bearer release request message to a second serving node after thefirst anchor node sends the RRC connection reconfiguration message tothe first serving node. A sequence for sending the bearer releaserequest message and sending the RRC connection reconfiguration messageis not specifically limited in the present invention.

Step 1002: The first serving node sends the RRC connectionreconfiguration message to first UE.

Specifically, the first RLC layer entity of the first serving node mayprocess the RRC connection reconfiguration message and then send aprocessed message to the first UE by using a MAC layer and a physicallayer.

Step 1003: The first serving node receives an RRC connectionreconfiguration complete message sent by the first UE.

Step 1004: The first serving node sends the RRC connectionreconfiguration complete message to the first anchor node.

The second indication information may be carried when the RRC connectionreconfiguration complete message is being sent. Specifically, the secondindication information may be carried in the RRC connectionreconfiguration complete message, or the second indication informationmay be carried in a control plane signaling message that carries the RRCconnection reconfiguration complete message. Alternatively, the secondindication information may be independently sent after the RRCconnection reconfiguration complete message is sent, so that the firstanchor node identifies, according to the second indication information,that the RRC connection reconfiguration message is the RRC messagecarried by the SRB1. A first PDCP layer entity of the first anchor nodeprocesses the RRC message carried by the SRB1 and then sends a processedmessage to an RRC layer entity.

Step 1005: The first serving node receives a bear addition/modificationcomplete message sent by the first anchor node.

It may be learned from the foregoing processing process that, in the RRCmessage processing method provided in this embodiment of the presentinvention, handover between serving nodes connected to an anchor nodemay be implemented. In addition, in a serving node handover process, foran RRC message between a first serving node and a first anchor node,indication information used to indicate an SRB type may be carried whenthe RRC message is being sent, or the indication information may beindependently sent, so that the first serving node and the first anchornode perform corresponding processing. Therefore, an RRC function isseparated to two nodes, namely, the first serving node and the firstanchor node.

FIG. 11 is a flowchart of an RRC message processing method on a servingnode side according to an embodiment of the present invention. The RRCmessage processing method is based on the network architecture shown inFIG. 1 , and is specifically used for handover between serving nodesconnected to anchor nodes. The method is executed by a serving node. TheRRC message includes an RRC message carried by an SRB1. The RRC messagecarried by the SRB1 is specifically an RRC connection reconfigurationmessage. As shown in FIG. 11 , the method specifically includes thefollowing steps.

Step 1101: A first serving node receives an RRC connectionreconfiguration message sent by a first anchor node, where the RRCconnection reconfiguration message is an RRC connection reconfigurationmessage that is sent by the first anchor node after a second anchor nodeor a neighboring base station receives a handover request message sentby the first anchor node and sends a handover request confirmationmessage to the first anchor node, and the first serving node belongs tothe first anchor node.

Second indication information may be carried when the RRC connectionreconfiguration message is being sent. Specifically, the secondindication information may be carried in the RRC connectionreconfiguration message, or the second indication information may becarried in a control plane signaling message that carries the RRCconnection reconfiguration message. Alternatively, the second indicationinformation may be independently sent after the RRC connectionreconfiguration message is sent, so that the first serving nodeidentifies, according to the second indication information, that the RRCconnection reconfiguration message is an RRC message carried by an SRB1.A first RLC layer entity of the first serving node processes the RRCconnection reconfiguration message.

The neighboring base station is a base station that is established in acell adjacent to a cell in which the first serving node is located. Inthis embodiment of the present invention, when a handover needs to beperformed on the first anchor node, the handover may be performed fromthe first anchor node to the second anchor node or to the neighboringbase station.

Step 1102: The first serving node sends the RRC connectionreconfiguration message to first UE.

Specifically, the first RLC layer entity of the first serving node mayprocess the RRC connection reconfiguration message and then send aprocessed message to the first UE by using a MAC layer and a physicallayer.

In addition, after step 1102, the first anchor node may send a bearerrelease request message to the first serving node.

In this embodiment of the present invention, the following processingprocess may further be included: The second anchor node or theneighboring base station processes a random access process of the firstUE; a second serving node or the neighboring base station receives anRRC connection reconfiguration complete message sent by the first UE;the second serving node sends the RRC connection reconfigurationcomplete message to the second anchor node; the first anchor nodereceives a UE context release request message sent by the second anchornode or the neighboring base station.

The second indication information may be carried when the RRC connectionreconfiguration complete message is being sent. Specifically, the secondindication information may be carried in the RRC connectionreconfiguration complete message, or the second indication informationmay be carried in a control plane signaling message that carries the RRCconnection reconfiguration complete message. Alternatively, the secondindication information may be independently sent after the RRCconnection reconfiguration complete message is sent, so that the secondanchor node identifies, according to the second indication information,that the RRC connection reconfiguration complete message is the RRCmessage carried by the SRB1. A first PDCP layer entity of the secondanchor node processes the RRC message carried by the SRB1 and then sendsa processed message to an RRC layer entity.

It may be learned from the foregoing processing process that, in the RRCmessage processing method provided in this embodiment of the presentinvention, handover between serving nodes connected to anchor nodes maybe implemented. In addition, in a serving node handover process, for anRRC message between a first serving node and a first anchor node,indication information used to indicate an SRB type may be carried whenthe RRC message is being sent, or the indication information may beindependently sent, so that the first serving node and the first anchornode perform corresponding processing. Therefore, an RRC function isseparated to two nodes, namely, the first serving node and the firstanchor node.

FIG. 12 is a flowchart of an RRC message processing method on a servingnode side according to an embodiment of the present invention. The RRCmessage processing method is based on the network architecture shown inFIG. 1 , and is specifically used for RRC connection re-setup after aradio link failure occurs. The method is executed by a serving node. TheRRC message includes an RRC message carried by an SRB0 and an RRCmessage carried by an SRB1. The RRC message carried by the SRB0 isspecifically an RRC connection re-setup request message or an RRCconnection re-setup message. The RRC message carried by the SRB1 isspecifically an RRC connection re-setup complete message. As shown inFIG. 12 , the method specifically includes the following steps.

Step 1201: A first serving node receives an RRC connection re-setuprequest message sent by first UE, where the RRC connection re-setuprequest message is an RRC connection re-setup request message that issent by the first UE after the first UE finds a radio link failure RLF,receives a system message sent by means of broadcast by the firstserving node, sends a random access message to the first serving nodeaccording to the system message, and receives a random access responsemessage sent by the first serving node.

Step 1202: The first serving node sends the RRC connection re-setuprequest message to a first anchor node.

In this embodiment of the present invention, the first serving node mayadd first indication information to a message when sending the RRCconnection re-setup request message to the first anchor node, andspecifically, may add the first indication information to the RRCconnection re-setup request message or add the first indicationinformation to a control plane signaling message that carries the RRCconnection re-setup request message. Alternatively, the first servingnode may independently send the first indication information aftersending the RRC connection re-setup request message. The firstindication information is used to indicate that the RRC connectionre-setup request message is an RRC message carried by an SRB0. The firstindication information may be an explicit signaling indication or aparticular message name. The latter is, for example, SRB0RRCTransfer orInitialRRCTransfer. Therefore, after identifying, according to the firstindication information, that the RRC connection re-setup request messageis the RRC message carried by the SRB0, the first anchor node directlydelivers the message to an RRC layer entity for processing.

Step 1203: The first serving node receives an RRC connection re-setupmessage sent by the first anchor node.

In this embodiment of the present invention, the first anchor node mayadd the first indication information to a message when sending the RRCconnection re-setup message to the first serving node, and specifically,may add the first indication information to the RRC connection re-setupmessage or add the first indication information to a control planesignaling message that carries the RRC connection re-setup message.Alternatively, the first anchor node may independently send the firstindication information after sending the RRC connection re-setupmessage, so that the first serving node identifies, according to thefirst indication information, that the RRC connection setup message isthe RRC message carried by the SRB0.

Step 1204: The first serving node sends the RRC connection re-setupmessage to the first UE.

Step 1205: The first serving node receives an RRC connection re-setupcomplete message sent by the first UE.

In this embodiment of the present invention, the first serving node hasa first RLC layer entity used to process an RRC message carried by anSRB1 and a second RLC layer entity used to process an RRC messagecarried by an SRB2. Because the RRC connection re-setup complete messageis the RRC message carried by the SRB1, the first RLC layer entity ofthe first serving node processes the RRC connection re-setup completemessage and then sends a processed message to the first UE.

Step 1206: The first serving node sends the RRC connection re-setupcomplete message to the first anchor node, to set up an RRC connectionfor the first anchor node and the first UE.

The first serving node may further send second indication informationwhen sending the RRC connection re-setup complete message to the firstanchor node, so that the first anchor node identifies, according to thesecond indication information, that the RRC connection re-setup completemessage is the RRC message carried by the SRB1. Then, a first PDCP layerentity of the first anchor node processes the RRC connection re-setupcomplete message and then sends a processed message to the RRC layerentity.

It may be learned from the foregoing processing process that, in the RRCmessage processing method provided in this embodiment of the presentinvention, RRC connection re-setup may be implemented after a radio linkfailure occurs. In addition, in an RRC connection re-setup process, foran RRC message between a first serving node and a first anchor node,indication information used to indicate an SRB type may be carried whenthe RRC message is being sent, or the indication information may beindependently sent, so that the first serving node and the first anchornode perform corresponding processing. Therefore, an RRC function isseparated to two nodes, namely, the first serving node and the firstanchor node.

FIG. 13 is a flowchart of an RRC message processing method on an anchornode side according to an embodiment of the present invention. The RRCmessage processing method is based on the network architecture shown inFIG. 1 . The method is executed by an anchor node. As shown in FIG. 13 ,the method specifically includes the following steps.

Step 1301: A first anchor node sends an RRC message to a first servingnode, where the RRC message includes an RRC message carried by an SRB1or an RRC message carried by an SRB2.

The first anchor node has an RRC function corresponding to the SRB1 andan RRC function corresponding to the SRB2.

Step 1302. The first anchor node receives an RRC message sent by thefirst serving node, and a first PDCP layer entity of the first anchornode processes an RRC message carried by the SRB1 and then sends aprocessed message to an RRC layer entity, or a second PDCP layer entityprocesses an RRC message carried by the SRB2 and then sends a processedmessage to the RRC layer entity.

The RRC message may further include an RRC message carried by an SRB0.The method may further include: receiving, by the first anchor node,first indication information sent by the first serving node, where thefirst indication information is used by the first anchor node toidentify, according to the first indication information, that the RRCmessage is the RRC message carried by the SRB0, and to performprocessing by using the RRC layer entity of the first anchor node; orsending, by the first anchor node, first indication information to thefirst serving node, where the first indication information is used bythe first serving node to identify, according to the first indicationinformation, that the RRC message is the RRC message carried by theSRB0, and to perform processing by using an RRC layer entity of thefirst serving node.

The method may further include: receiving, by the first anchor node,second indication information sent by the first serving node, where thesecond indication information is used by the first anchor node toidentify, according to the second indication information, that the RRCmessage is the RRC message carried by the SRB1; or sending, by the firstanchor node, second indication information to the first serving node,where the second indication information is used by the first servingnode to identify, according to the second indication information, thatthe RRC message is the RRC message carried by the SRB1.

The method may further include: receiving, by the first anchor node,third indication information sent by the first serving node, where thethird indication information is used by the first anchor node toidentify, according to the third indication information, that the RRCmessage is the RRC message carried by the SRB2; or sending, by the firstanchor node, third indication information to the first serving node,where the third indication information is used by the first serving nodeto identify, according to the third indication information, that the RRCmessage is the RRC message carried by the SRB2.

It may be learned from the foregoing processing process that, in the RRCmessage processing method provided in this embodiment of the presentinvention, an RRC message cannot be directly sent between first UE and afirst anchor node, and needs to be forwarded by a first serving node.That is, when the first UE needs to send an RRC message to the firstanchor node, the first UE first needs to send the RRC message to thefirst serving node, and then the first serving node sends the RRCmessage to the first anchor node. When the first anchor node needs tosend an RRC message to the first UE, the first anchor node first needsto send the RRC message to the first serving node, and then the firstserving node sends the RRC message to the first UE. Because the RRCmessage needs to pass through two nodes, namely, the first anchor nodeand the first serving node, an RRC function can be separated to twonodes by using the method provided in Embodiment 1 of the presentinvention.

FIG. 14 is a flowchart of an RRC message processing method on an anchornode side according to an embodiment of the present invention. The RRCmessage processing method is based on the network architecture shown inFIG. 1 , and is specifically used to set up an RRC connection. Themethod is executed by an anchor node. The RRC message includes an RRCmessage carried by an SRB1, an RRC message carried by an SRB2, and anRRC message carried by an SRB0. The RRC message carried by the SRB0 isspecifically an RRC connection request message or an RRC connectionsetup message. The RRC message carried by the SRB1 is specifically anRRC connection setup complete message. As shown in FIG. 14 , the methodspecifically includes the following steps.

Step 1401: A first anchor node receives an RRC connection requestmessage forwarded by a first serving node, where the RRC connectionrequest message is an RRC connection request message that is sent by thefirst UE to the first serving node after the first UE receives a systemmessage sent by means of broadcast by the first serving node, sends arandom access message to the first serving node according to the systemmessage, and receives a random access response message sent by the firstserving node.

Step 1402: The first anchor node generates an RRC connection setupmessage according to the RRC connection request message.

Step 1403: The first anchor node sends the RRC connection setup messageto the first serving node, so that the first serving node sends the RRCconnection setup message to the first UE.

Step 1404: The first anchor node receives an RRC connection setupcomplete message sent by the first serving node, to set up an RRCconnection for the first anchor node and the first UE, where the RRCconnection setup complete message is an RRC connection setup completemessage that is sent by the first UE to the first serving node after thefirst UE receives the RRC connection setup message.

It may be learned from the foregoing processing process that, in the RRCmessage processing method provided in this embodiment of the presentinvention, an RRC connection may be set up for a first anchor node andfirst UE. In addition, in a process of setting up the RRC connection,for an RRC message between a first serving node and the first anchornode, indication information used to indicate an SRB type may be carriedwhen the RRC message is being sent, or the indication information may beindependently sent, so that the first serving node and the first anchornode perform corresponding processing. Therefore, an RRC function isseparated to two nodes, namely, the first serving node and the firstanchor node.

FIG. 15 is a flowchart of an RRC message processing method on an anchornode side according to an embodiment of the present invention. The RRCmessage processing method is based on the network architecture shown inFIG. 1 , and is specifically used to set up a DRB bearer. The method isexecuted by an anchor node. The RRC message includes an RRC messagecarried by an SRB1. The RRC message carried by the SRB1 is specificallyan RRC connection reconfiguration message or an RRC connectionreconfiguration complete message. As shown in FIG. 15 , the methodspecifically includes the following steps.

Step 1501: A first anchor node receives a bearer addition/modificationconfirmation message sent by a first serving node, where the beareraddition/modification confirmation message is the beareraddition/modification confirmation message that is generated by thefirst serving node according to a bearer addition/modification requestmessage after the first anchor node sends the beareraddition/modification request message to the first serving node.

Step 1502: The first anchor node sends an RRC connection reconfigurationmessage to the first serving node, so that the first serving node sendsthe RRC connection reconfiguration message to first UE.

Step 1503: The first anchor node receives an RRC connectionreconfiguration complete message sent by the first serving node, wherethe RRC connection reconfiguration complete message is the RRCconnection reconfiguration complete message that is sent by the first UEto the first serving node after the first UE receives the RRC connectionreconfiguration message; the first anchor node sends a beareraddition/modification complete message to the first serving nodeaccording to the RRC connection reconfiguration complete message.

It may be learned from the foregoing processing process that, in the RRCmessage processing method provided in this embodiment of the presentinvention, a DRB bearer may be set up. In addition, in a process ofsetting up the DRB bearer, for an RRC message between a first servingnode and a first anchor node, indication information used to indicate anSRB type may be carried when the RRC message is being sent, or theindication information may be independently sent, so that the firstserving node and the first anchor node perform corresponding processing.Therefore, an RRC function is separated to two nodes, namely, the firstserving node and the first anchor node.

FIG. 16 is a flowchart of an RRC message processing method on an anchornode side according to an embodiment of the present invention. The RRCmessage processing method is based on the network architecture shown inFIG. 1 , and is specifically used for handover between serving nodesconnected to an anchor node. The method is executed by an anchor node.The RRC message includes an RRC message carried by an SRB1. The RRCmessage carried by the SRB1 is specifically an RRC connectionreconfiguration message or an RRC connection reconfiguration completemessage. As shown in FIG. 16 , the method specifically includes thefollowing steps.

Step 1601: A first anchor node sends an RRC connection reconfigurationmessage to a first serving node, where the RRC connectionreconfiguration message is the RRC connection reconfiguration messagethat is sent by the first anchor node to the first serving node afterthe first anchor node sends a bearer addition/modification requestmessage to the first serving node and receives a beareraddition/modification confirmation message sent by the first servingnode.

Step 1602: The first anchor node receives an RRC connectionreconfiguration complete message sent by the first serving node, wherethe RRC connection reconfiguration complete message is the RRCconnection reconfiguration complete message that is sent by the first UEand that is received by the first serving node after the first servingnode receives the RRC connection reconfiguration message sent by thefirst anchor node and sends the RRC connection reconfiguration messageto the first UE.

Step 1603: The first anchor node sends a bear addition/modificationcomplete message to the first serving node.

It may be learned from the foregoing processing process that, in the RRCmessage processing method provided in this embodiment of the presentinvention, handover between serving nodes connected to an anchor nodemay be implemented. In addition, in a serving node handover process, foran RRC message between a first serving node and a first anchor node,indication information used to indicate an SRB type may be carried whenthe RRC message is being sent, or the indication information may beindependently sent, so that the first serving node and the first anchornode perform corresponding processing. Therefore, an RRC function isseparated to two nodes, namely, the first serving node and the firstanchor node.

FIG. 17 is a flowchart of an RRC message processing method on an anchornode side according to an embodiment of the present invention. The RRCmessage processing method is based on the network architecture shown inFIG. 1 , and is specifically used for handover between serving nodesconnected to anchor nodes. The method is executed by an anchor node. TheRRC message includes an RRC message carried by an SRB1. The RRC messagecarried by the SRB1 is specifically an RRC connection reconfigurationmessage. As shown in FIG. 12 , the method specifically includes thefollowing step.

Step 1701: A first anchor node sends an RRC connection reconfigurationmessage to a first serving node, so that the first serving node sendsthe RRC connection reconfiguration message to first UE, where the RRCconnection reconfiguration message is the RRC connection reconfigurationmessage that is sent by the first anchor node after a second anchor nodeor a neighboring base station receives a handover request message sentby the first anchor node and sends a handover request confirmationmessage to the first anchor node, and the first serving node belongs tothe first anchor node.

It may be learned from the foregoing processing process that, in the RRCmessage processing method provided in this embodiment of the presentinvention, handover between serving nodes connected to anchor nodes maybe implemented. In addition, in a serving node handover process, for anRRC message between a first serving node and a first anchor node,indication information used to indicate an SRB type may be carried whenthe RRC message is being sent, or the indication information may beindependently sent, so that the first serving node and the first anchornode perform corresponding processing. Therefore, an RRC function isseparated to two nodes, namely, the first serving node and the firstanchor node.

FIG. 18 is a flowchart of an RRC message processing method on an anchornode side according to an embodiment of the present invention. The RRCmessage processing method is based on the network architecture shown inFIG. 1 , and is specifically used for RRC connection re-setup after aradio link failure occurs. The method is executed by an anchor node. TheRRC message includes an RRC message carried by an SRB0 and an RRCmessage carried by an SRB1. The RRC message carried by the SRB0 isspecifically an RRC connection re-setup request message or an RRCconnection re-setup message. The RRC message carried by the SRB1 isspecifically an RRC connection re-setup complete message. As shown inFIG. 18 , the method specifically includes the following steps.

Step 1801: A first anchor node receives an RRC connection re-setuprequest message sent by a first serving node, where the RRC connectionre-setup request message is the RRC connection re-setup request messagethat is sent by the first UE to the first serving node after the firstUE finds a radio link failure RLF, receives a system message sent bymeans of broadcast by the first serving node, sends a random accessmessage to the first serving node according to the system message, andreceives a random access response message sent by the first servingnode.

Step 1802: The first anchor node sends an RRC connection re-setupmessage to the first serving node, so that the first serving node sendsthe RRC connection re-setup message to the first UE.

Step 1803: The first anchor node receives an RRC connection re-setupcomplete message sent by the first serving node, to set up an RRCconnection for the first anchor node and the first UE, where the RRCconnection re-setup complete message is the RRC connection re-setupcomplete message that is sent by the first UE and received by the firstserving node.

It may be learned from the foregoing processing process that, in the RRCmessage processing method provided in this embodiment of the presentinvention, RRC connection re-setup may be implemented after a radio linkfailure occurs. In addition, in an RRC connection re-setup process, foran RRC message between a first serving node and a first anchor node,indication information used to indicate an SRB type may be carried whenthe RRC message is being sent, or the indication information may beindependently sent, so that the first serving node and the first anchornode perform corresponding processing. Therefore, an RRC function isseparated to two nodes, namely, the first serving node and the firstanchor node.

A person skilled in the art may be further aware that, in combinationwith the examples described in the embodiments disclosed in thisspecification, units and algorithm steps may be implemented byelectronic hardware, computer software, or a combination thereof. Toclearly describe the interchangeability between the hardware and thesoftware, the foregoing has generally described compositions and stepsof each example according to functions. Whether the functions areperformed by hardware or software depends on particular applications anddesign constraint conditions of the technical solutions. A personskilled in the art may use different methods to implement the describedfunctions for each particular application, but it should not beconsidered that the implementation goes beyond the scope of the presentinvention.

Steps of methods or algorithms described in the embodiments disclosed inthis specification may be implemented by hardware, a software moduleexecuted by a processor, or a combination thereof. The software modulemay reside in a random access memory (RAM), a memory, a read-only memory(ROM), an electrically programmable ROM, an electrically erasableprogrammable ROM, a register, a hard disk, a removable disk, a CD-ROM,or any other form of storage medium known in the art.

In the foregoing specific implementation manners, the objective,technical solutions, and benefits of the present invention are furtherdescribed in detail. It should be understood that the foregoingdescriptions are merely specific implementation manners of the presentinvention, but are not intended to limit the protection scope of thepresent invention. Any modification, equivalent replacement, orimprovement made without departing from the spirit and principle of thepresent invention should fall within the protection scope of the presentinvention.

What is claimed is:
 1. A system for processing a radio resource control(RRC) message, the system comprising: a serving node; and an anchornode, wherein the serving node and the anchor node are connected;wherein the serving node is configured to: receive a first radioresource control (RRC) message via an established signaling radio bearer(SRB) from a user equipment (UE); and send the first RRC message andfirst indication information to the anchor node, wherein the firstindication information identifies the established SRB.
 2. The systemaccording to claim 1, wherein the SRB that carries the first RRC messageis SRB 0, SRB 1, or SRB
 2. 3. The system according to claim 2, whereinthe anchor node is configured to: send a second RRC message and secondindication information to the serving node, wherein the secondindication information identifies a second SRB that carries the secondRRC message from the anchor node.
 4. The system according to claim 3,wherein the second SRB that carries the second RRC message is SRB 0, SRB1, or SRB
 2. 5. The system according to claim 3, wherein the second RRCmessage is carried by SRB 1 or SRB 2, and the serving node is configuredto: obtain a processed message by processing, by a Radio Link Control(RLC) layer entity of the serving node, the second RRC message carriedby the SRB 1 or the SRB 2; and send the processed message to the UE. 6.The system according to claim 1, wherein the first RRC message iscarried by SRB 1 or SRB 2, and the anchor node is configured to: obtaina processed message by processing, by a Packet Data Convergence Protocol(PDCP) layer entity of the anchor node and an RRC layer of the anchornode, the first RRC message carried by the SRB 1 or the SRB 2; and sendthe processed message to the serving node.
 7. The system according toclaim 3, wherein the second RRC message is one message of an RRCconnection setup message carried by an SRB 0, an RRC connectionreestablishment message carried by the SRB 0, or an RRC connectionreconfiguration message carried by SRB 1, and the serving node isconfigured to: send the second RRC message to the UE.
 8. The systemaccording to claim 1, wherein the first RRC message from the UE is onemessage of an RRC connection reestablishment complete message carried bySRB 1, an RRC connection reconfiguration complete message carried by SRB1, or an RRC connection setup complete message carried by SRB 1, and theserving node is configured to: send the first RRC message to the anchornode.
 9. A method for processing a radio resource control (RRC) messagein a communication system, the communication system comprising: aserving node and an anchor node, wherein the serving node and the anchornode are connected, the method comprising: receiving, by the servingnode, a first radio resource control (RRC) message via an establishedsignaling radio bearer (SRB) from a user equipment (UE); and sending, bythe serving node, the first RRC message and first indication informationto the anchor node, wherein the first indication information identifiesthe established SRB.
 10. The method according to claim 9, wherein theSRB that carries the first RRC message is SRB 0, SRB 1, or SRB
 2. 11.The method according to claim 10, wherein the method further comprise:sending, by the anchor node, a second RRC message and second indicationinformation to the serving node, the second indication informationidentifies a second SRB that carries the second RRC message from theanchor node.
 12. The method according to claim 11, wherein the secondSRB that carries the second RRC message is SRB 0, SRB 1, or SRB
 2. 13.The method according to claim 11, wherein the second RRC message iscarried by SRB 1 or SRB 2, and the method further comprises: obtaining aprocessed message by processing, by a Radio Link Control (RLC) layerentity of the serving node, the second RRC message carried by the SRB 1or the SRB 2; and sending, by the serving node, the processed message tothe UE.
 14. The method according to claim 9, wherein the first RRCmessage is carried by SRB 1 or SRB 2, and the method further comprises:obtaining a processed message by processing, by a Packet DataConvergence Protocol (PDCP) layer entity of the anchor node and an RRClayer of the anchor node, the first RRC message carried by the SRB 1 orthe SRB 2; and sending, by the anchor node, the processed message to theserving node.
 15. The method according to claim 11, wherein the secondRRC message is one message of an RRC connection setup message carried byan SRB 0, an RRC connection reestablishment message carried by the SRBor an RRC connection reconfiguration message carried by SRB 1, and themethod further comprises: sending, by the serving node, the second RRCmessage to the UE.
 16. The method according to claim 9, wherein thefirst RRC message from the UE is one message of an RRC connectionreestablishment complete message carried by SRB 1, an RRC connectionreconfiguration complete message carried by SRB 1, or an RRC connectionsetup complete message carried by SRB 1, and the method furthercomprises: sending, by the serving node, the first RRC message to theanchor node.